Dictionary (O-R)

Term

Abbreviations

Definition

Labels

Synonyms

OAuth

OAuth is an open standard authorization protocol that enables third-party applications to obtain limited access to user accounts on an HTTP service, without compromising the user's password. OAuth 2.0, which provides greater flexibility and scalability than OAuth 1.0, has become a leading choice for authentication in web, mobile, and desktop applications.

tech

Obfuscation

In software development, obfuscation is the practice of creating source or machine code that is intentionally difficult for humans or computers to understand. Similar to obfuscation in natural language, code obfuscation may involve using unnecessarily roundabout ways to write statements. Programmers often obfuscate code to conceal its purpose, logic, or embedded values. The primary reasons for doing so are to prevent tampering or deter reverse engineering. While obfuscation can be done manually, it is more commonly performed using obfuscators.

tech

Observer pattern

In software design and software engineering, the observer pattern is a software design pattern in which an object, called the subject (also known as event source or event stream), maintains a list of its dependents, called observers (also known as event sinks), and automatically notifies them of any state changes, typically by calling one of their methods. The subject knows its observers through a standardised interface and manages the subscription list directly. This pattern creates a one-to-many dependency where multiple observers can listen to a single subject, but the coupling is typically synchronous and direct—the subject calls observer methods when changes occur, though asynchronous implementations using event queues are possible. Unlike the publish-subscribe pattern, there is no intermediary broker; the subject and observers have direct references to each other. It is commonly used to implement event handling systems in event-driven programming, particularly in-process systems like GUI toolkits or MVC frameworks. This makes the pattern well-suited to processing data that arrives unpredictably—such as user input, HTTP requests, GPIO signals, updates from distributed databases, or changes in a GUI model.

tech

ODBC: Open Database Connectivity

ODBC

Open Database Connectivity (ODBC) is a C language standard application programming interface (API) for accessing database management systems (DBMS). The designers of ODBC aimed to make it independent of database systems and operating systems. An application written using ODBC can be ported to other platforms, both on the client and server side, with few changes to the data access code. ODBC accomplishes DBMS independence by using an ODBC driver as a translation layer between the application and the DBMS. The application uses ODBC functions through an ODBC driver manager with which it is linked, and the driver passes the query to the DBMS. An ODBC driver can be thought of as analogous to a printer driver or other driver, providing a standard set of functions for the application to use, and implementing DBMS-specific functionality. An application that can use ODBC is referred to as 'ODBC-compliant'. Any ODBC-compliant application can access any DBMS for which a driver is installed. Drivers exist for all major DBMSs, many other data sources like address book systems and Microsoft Excel, and even for text or comma-separated values (CSV) files. A bridge is a special kind of driver: a driver that uses another driver-based technology (e.g., ODBC-JDBC bridges, JDBC-ODBC bridges, OLE DB-ODBC bridges, ADO.NET-ODBC bridges).

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OBBC, Open Database Connectivity

OFAC: Office of Foreign Assets Control

OFAC

The agency within the US Department of the Treasury responsible for administering and enforcing economic sanctions issued as part of US foreign policy and by international organizations like the United Nations against targeted foreign countries. It often works in consultation with other agencies, such as the Department of State, to oversee national security goals. A core component of the agency's responsibilities is the creation and maintenance of the Specially Designated Nationals (SDN) list.

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OFAC, Office of Foreign Assets Control

Offline card transaction

A card transaction which is authorised without contacting the issuer at the time of the transaction. Antonym: online card transaction .

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Offshore

Literally, away from one's own home country—if one lives in Europe, the United States is \"offshore.\" In the money laundering lexicon, the term refers to jurisdictions deemed favourable to foreign investments because of low or no taxation or strict bank secrecy regulations.

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Omnibus Account

An omnibus account refers to an investment account shared by multiple individuals. An omnibus account allows for managed trades of more than one person, and allows for anonymity of the persons in the account. Omnibus accounts allow more efficient transactions to take place, since the manager can act swiftly when market conditions call for it. Also, the manager's compensation is often tied to the performance of the omnibus account, adding incentive to have it perform well. For investors that want privacy, an omnibus account is beneficial.

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Online Banking

Online Banking allows users to complete financial transactions on the Internet instead of at a bank or credit union. It is faster, more convenient, and available anywhere, at any time. Online banking is done from a desktop or laptop, whilst mobile banking takes place on a portable electronic device like a smartphone or a tablet.

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Online card transaction

A card transaction which is authorised following explicit approval by the issuer at the time of the transaction. Antonym: offline card transaction .

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OOP: Object oriented programming languages

An object-oriented programming (OOP) language turns everything into objects. Each object — which is a unique piece of data — is defined by its attributes & methods, & assigned to a particular class. Rather than designing a language around functions & logic, object-oriented programming allows developers to directly manipulate data. These languages use principles like inheritance, encapsulation, polymorphism and abstraction to model real-world entities & relationships, making code more modular, reusable & easier to maintain. It’s frequently used in software, web & game development as well as simulation modelling & artificial intelligence applications. Examples: Java Python PHP C++ Ruby Use cases: Large or complex software applications Web development AI applications

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OOP, Object oriented programming languages, Object-oriented programming languages

OOP: Object-Oriented Programming

OOP

Object-Oriented Programming (OOP) is a programming paradigm that organizes code around objects, which are instances of classes. It emphasizes concepts such as encapsulation, inheritance, and polymorphism. OOP allows modular and reusable code, promotes code organisation, and facilitates software maintenance and extensibility.

tech

OOP, Object-Oriented Programming

Open Banking

Open banking is a way of giving regulated companies, secure, limited access to your bank account, with your permission, so that they can provide services that are helpful to you. For example, budgeting advice, or recommendations for other financial products that you are eligible for. So, Open banking is the secure sharing of financial data between financial institutions, such as ISX. Before open banking became available, consumer financial data was controlled solely by big banks. Now, consumers are able to access, and manage, their financial data across our platforms — resulting in a smoother, more personalised experience in the process. This benefits our customers, who end up paying lower costs whilst enjoying improved technology and customer service.

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Operational risk

The risk of negative financial, business and/or reputational impacts resulting from inadequate or failed internal governance and business processes, people, systems, or from external events.

legal

Optimisation routine

A procedure determining the order in which transfer orders are to be processed and settled in a transfer system in order to increase settlement efficiency.

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OPTIONS Method

This HTTP method describes the communication options for the target resource.

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OR

A Boolean operation that outputs True if either or both input values are True.

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ORC: Optimised Row Columnar

ORC

Optimized Row Columnar (ORC) is a high-performance, open-source columnar storage format for Apache Hadoop workloads, designed to optimize read, write, and processing speed. It reduces file sizes by up to 75% compared to text formats using columnar storage, compression (Snappy, Zlib), and lightweight indexing. ORC supports complex data types and is ideal for Apache Hive, Spark, and big data analytics.

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ORC, Optimized Row Columnar, Optimised Row Columnar

Originator

An originator (initiator or payer) refers to the party of a payment transaction which issues the payment order or agrees to the transfer of funds to a payee

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Initiator, Payer, Originator

OS Command Injection

OS command injection is also known as shell injection. It allows an attacker to execute operating system (OS) commands on the server that is running an application, and typically fully compromise the application and its data. Often, an attacker can leverage an OS command injection vulnerability to compromise other parts of the hosting infrastructure, and exploit trust relationships to pivot the attack to other systems within the organisation.

tech

OS Command Injection, Shell Injection, Operating System Command Injection

OTP: One-Time Password

OTP

One-Time Password is an automatically generated numeric or alphanumeric string of characters that authenticates a user for a single transaction or login session. An OTP is more secure than a static password, especially a user-created password, which can be weak and/or reused across multiple accounts. OTPs may replace authentication login information or may be used in addition to it to add another layer of security.

tech

OTP, One-Time Password, One Time Password

Overdraft

An overdraft refers to an extension of credit from a financial institution to its customer when they execute a transaction for which the account holder has insufficient funds. An overdraft occurs when an account lacks the funds to cover a withdrawal, but the bank allows the transaction to go through anyway. The overdraft allows the customer to continue paying bills even when there is insufficient money in their account. Many banks impose additional fees or penalties for overdrawn accounts. An overdraft is like any other loan: the account holder pays interest on it and will typically be charged a one-time insufficient funds fee. Overdraft protection is provided by some banks to customers when their account reaches zero; it avoids insufficient funds charges, but often includes interest and other fees.

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Owner’s Equity

Owner’s equity (capital) refers to assets left over after subtracting liabilities from assets (e.g., common stock, owner draws, net profits & retained earnings).

fin

Owner’s Equity, Capital

P-Value: Probability Value

P-Value

A p-value, or probability value, is a statistical measure describing the likelihood of obtaining the observed data under the null hypothesis of a statistical test (i.e., used to determine the likelihood that an observed outcome is the result of chance). A p-value is a statistical measurement used to validate a hypothesis against observed data. A p-value measures the probability of obtaining the observed results, assuming that the null hypothesis is true. The lower the p-value, the greater the statistical significance of the observed difference. A p-value of 0.05 or lower is generally considered statistically significant. P-value can serve as an alternative to—or in addition to—preselected confidence levels for hypothesis testing.

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P-Value, Probability Value

P2P: Peer-to-Peer Service

P2P

P2P is a decentralised platform whereby two individuals interact directly with each other, without intermediation by a third party. Instead, a buyer and a seller transact directly with each other via the P2P service.

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P2P, Peer-to-Peer Service

PaaS: Platform-as-a-Service

PaaS

Platform-as-a-Service is considered the most complex of the three layers of cloud computing. PaaS shares some similarities with SaaS, the primary difference being that instead of delivering software online, it is actually a platform for creating software that is delivered via the Internet.

tech

PaaS, Platform-as-a-Service

PaidBy

PaidBy transfers connect a business directly to both the UK’s & the EU’s banking network, meaning that customers can pay directly from their bank accounts, instantly, using open banking.

product

PaidBy Global

PaidBy Global enables cross-border Open Banking payments that allow end users in Europe and the UK to pay merchants globally using their local bank accounts in EUR or GBP, whilst merchants receive settlements in their preferred currency (e.g., AUD, CAD, CHF, HKD, NZD, PLN, USD).

product

PAN: Primary Account Number

PAN

A payment card number is the card identifier found on payment cards, such as credit cards and debit cards. In some situations the card number is referred to as a bank card number. The card number is primarily a card identifier and may not directly identify the bank account number(s) to which the card is/are linked by the issuing entity. The card number prefix identifies the issuer of the card, and the digits that follow are used by the issuing entity to identify the cardholder as a customer and which is then associated by the issuing entity with the customer's designated bank accounts. Card numbers are allocated in accordance with ISO/IEC 7812. The card number is typically embossed on the front of a payment card, and is encoded on the magnetic stripe and chip, but may also be imprinted on the back of the card. A PAN is typically made up of 16 digits, but it can vary from 12 to 19 numbers.

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PAN, Payment Card Number, Primary Account Number, Card Number

Parameters

Params

Special types of variables used in computer programming to pass data between procedures and functions. An argument to a function is referred to as a parameter. Adding three numbers, for example, may require three parameters.

tech

Parameters, Params

Parametric Test

Parametric tests are statistical tests that assume the data follows a certain distribution (e.g., normal distribution).

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Parquet

Apache Parquet is an open-source, column-oriented data file format designed for efficient data storage and high-performance retrieval in big data analytics. By storing data by columns rather than rows, it enables superior compression, reduced storage costs, and faster query performance for analytical workloads (OLAP). Parquet supports complex data types and is a standard for Hadoop, Spark, and data lake architectures.

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Participant

An entity which is identified/recognised by a transfer system and – either directly or indirectly – is allowed to send transfer orders to that system and is capable of receiving transfer orders from it.

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Partitioning

Partitioning divides a large database table into smaller, manageable chunks based on a specific criterion (e.g., date, region). Why use partitioning? • Improves query performance by scanning only relevant partitions. • Helps manage large datasets efficiently.

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Pascal Case

A common naming convention that is similar to Camel Case, but the first word also starts with a capital letter. Example: Customer, GetByld

tech

PATCH Method

This HTTP method is used to apply partial modifications to a resource.

tech

Path

The resource URL that API developers choose to expose their API. Each path can have a GET, PUT, POST, or DELETE HTTP action defined.

tech

Paydentity

Paydentity is an ISX solution that allows for customer onboarding, KYC & due diligence of individuals, sanction/PEP screening, as well as AML/CFT checks.

product

Payer

The party to a payment transaction which issues the payment order or agrees to the transfer of funds to the payee.

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Payment

In a strict sense, a payment is a transfer of funds which discharges an obligation on the part of a payer vis-à-vis a payee. However, in a technical or statistical sense, it is often used as a synonym for “transfer order”.

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Payment, Transfer Order

Payment card

A payment instrument, which is based on the rules of a card scheme, used to withdraw or place cash and/or enable a transfer of value at the request of the payer (via the payee) or the payee in respect of an end-user account linked to the card.

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Payment Gateway

A service provided by Electronic Money Institutions that allows online merchants to accept electronic payments from customers.

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Payment integration services

A technical integration of several payment services in a merchant platform.

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Payment Intermediary Service Provider

A payment service provider that is not the payment service provider of the payer or the payee and receives and transmits a transfer of funds on behalf of the payment service provider of the payer or of the payee or of another intermediary payment service provider per the Regulation (EU) 2015/847 of the European Parliament and of the Council of 20 May 2015 on information accompanying transfers of funds and repealing Regulation (EC) No. 1781/2006.

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Payment service provider

A natural or legal person providing services (e.g., issuing, acquiring, the authorisation of transactions, the authentication of end users) enabling the transfer of value between end users. This also includes crypto-asset service providers when delivering services relating to digital payment tokens.

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Payment Service User

A natural or legal person making use of a payment service in the capacity of payer, payee, or both per the Directive (EU) 2015/2366 of the European Parliament and of the Council of 25 November 2015 on payment services in the internal market.

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Payment system

This term has two meanings. 1) In some cases, it refers to the set of instruments, banking procedures and interbank funds transfer systems which facilitate the circulation of money in a country or currency area. 2) In most cases, it is used as a synonym for “funds transfer system”.

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PayPlus

PayPlus is a web-based core banking solution.

system

PCI DSS: Payment Card Industry (PCI) Data Security Standard (DSS)

PCI DSS

Payment Card Industry Data Security Standard is a widely accepted set of policies and procedures intended to optimise the security of credit, debit, and cash card transactions and protect cardholders against misuse of their personal information.

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PCI DSS, Payment Card Industry Data Security Standard

PE-ACH: Pan-European Automated Clearing House

PE-ACH

A business platform for the processing of euro payment instruments which is made up of governance rules and payment practices and supported by the necessary technical platform(s).

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PE-ACH, Pan-European Automated Clearing House

Pearson Correlation Coefficient

The Pearson correlation coefficient measures the linear correlation between two variables, producing a value between -1 and 1. The Pearson correlation coefficient, often denoted as r, is a statistical measure that quantifies the strength and direction of a linear relationship between two variables. It ranges from -1 to 1, where: • 1 indicates a perfect positive linear relationship: As one variable increases, the other increases proportionally. • -1 indicates a perfect negative linear relationship: As one variable increases, the other decreases proportionally. • 0 indicates no linear relationship: There's no discernible linear trend between the variables.

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PEM: Privacy-Enhanced Mail

PEM

Privacy-Enhanced Mail is a de facto file format for storing and sending cryptographic keys, certificates, and other data, based on a set of 1993 IETF standards defining \"privacy-enhanced mail\". While the original standards were never broadly adopted and were supplanted by PGP and S/MIME, the textual encoding they defined became very popular. The PEM format was eventually formalised by the IETF in RFC 7468.

tech

PEM, Privacy-Enhanced Mail

Penetration Testing

Also known as pen testing or ethical hacking, simulates attacks on a computer system to identify exploitable vulnerabilities. This type of testing identifies, tests, and highlights vulnerabilities in an organisation’s security posture. Web application firewalls (WAF) are generally augmented by penetration testing in the context of web application security.

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PEP: Politically Exposed Person

PEP

Politically Exposed Person, in financial regulation, is a term describing someone who has been entrusted with a prominent public function. A PEP generally presents a higher risk for potential involvement in bribery and corruption by virtue of his or her position and the influence that the person may hold. The terms “politically exposed person” and senior foreign political figure are often used interchangeably, particularly in international forums. PEP screening is the process of identifying and assessing individuals who hold prominent public positions or have close associations with such individuals.

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PEP Screeing, Senior Foreign Political Figure, PEP

PER: Packed Encoding Rules

PER

Packed Encoding Rules refer to an ASN.1 wire format.

tech

PER, Packed Encoding Rules

Percentile

Percentile is a measure used to express the relative position of a score within a dataset. It indicates the percentage of scores that fall at or below a specific value. For example, the 80th percentile means 80% of the data is at or below that value. It is a way to understand a data point's relative position within a distribution.

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Permissioned blockchain

A private, permissioned blockchain restricts access to a select group of authorized participants. Only authorized users can read, write or validate transactions. These blockchains are often used for greater privacy, control, and efficiency as governance is managed by a central entity or consortium.

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Persistence

Persistence is a quality of data that indicates that the state will outlive the process that created it. Persistence is a key part of most database systems and allows the data to be loaded once again after the database process or the server itself is restarted. Applications and databases can have various levels of persistence that guard against different types of failure conditions like single system persistence, remote persistence, and cluster persistence.

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Phishing Scam

Phishing is a form of cyber-attack where attackers impersonate legitimate organizations or individuals to trick recipients into revealing sensitive information, such as login credentials, credit card numbers, or personal details. Phishing scams typically involve fraudulent emails, text messages, or websites designed to appear genuine, often prompting recipients to click on malicious links, download malicious attachments, or enter sensitive information into fake forms.

aml

Pig Butchering

A type of scam where fraudsters manipulate victims into making investments in fake or fraudulent schemes, often by building a sense of trust and then gradually encouraging larger investments. The term refers to the way scammers “fatten up” their victims by gaining their confidence and getting them to invest more before ultimately stealing the accumulated funds. This scam is increasingly relevant in the context of AML as it often involves laundering the stolen money through various channels.

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PIN: Personal Identification Number

PIN

A personal and confidential numerical code which the user of a payment instrument may need to use in order to verify his/her identity. In electronic transactions, this is seen as the equivalent of a signature.

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PIN, Personal Identification Number

PISP: Payment Initiation Service Provider

PISP

A Payment Initiation Service Provider (PISP) is an authorised third-party provider (under PSD2/Open Banking) that initiates online bank-to-bank payments directly from a customer's account, bypassing traditional card networks.

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PISP, Payment Initiation Service Provider

PIV: Payment Instrument Verification

PIV

Payment Instrument Verification, the ISX-patented method, uses the transaction value at the point of sale, such that the sales amount as agreed between the eMerchant and cardholder, is split into two (or more) amounts, with the first amount being a randomly generated value, and the second value being the balancing amount between sales amount and the random value.

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PIV, Payment Instrument Verification

Placement

The first phase of the classic three-step money laundering process before layering, placement involves the physical disposal of proceeds derived from illegal activity.

aml

Plaintext

Plaintext is intelligible data that has meaning and can be read or acted upon without the application of decryption. Also known as cleartext.

tech

Cleartext, Plaintext

POA: Proof of Address

POA

Proof of address is a document that confirms your current place of residence. Utility bills, bank statements, and government letters are commonly used as proof of address. Proof of address must match your ID name, show your current address, be issued by a recognised authority, and be dated within 3 to 12 months, depending on the type of document.

aml, fin

POA, Proof of Address

POI: Proof of Identity

POI

Proof of identity is a document or documents used to verify someone's identity. An identity document asserts a unique single civil identity and defines such person's identity in relation to the issuing state.

aml, fin

POI, Proof of Identity, Proof of Identification

Pointer

A pointer is an object in many programming languages that stores a memory address. This can be that of another value located in computer memory, or in some cases, that of memory-mapped computer hardware. A pointer references a location in memory, and obtaining the value stored at that location is known as dereferencing the pointer. As an analogy, a page number in a book's index could be considered a pointer to the corresponding page; dereferencing such a pointer would be done by flipping to the page with the given page number and reading the text found on that page. The actual format and content of a pointer variable is dependent on the underlying computer architecture. Using pointers significantly improves performance for repetitive operations, like traversing iterable data structures (e.g., strings, lookup tables, control tables, linked lists & tree structures). In particular, it is often much cheaper in time and space to copy and dereference pointers than it is to copy and access the data to which the pointers point.

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Poisson Distribution

The Poisson distribution is a probability distribution that is used to show how many times an event is likely to occur over a specified period. It is named after French mathematician Siméon Denis Poisson and it can be used to estimate how many times an event is likely to occur within 'x' periods. It is used when the variable of interest is a discrete count variable. Many economic and financial data appear as count variables, such as how many times a person becomes unemployed in a given year, or how many trades are made in one session, thus lending themselves to analysis using this. It is used by investment analysts in stochastic modelling.

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Polymorphism

In programming language theory and type theory, polymorphism allows a value type to assume different types. In object-oriented programming, polymorphism is the provision of one interface to entities of different data types. The concept is borrowed from a principle in biology in which an organism or species can have many different forms or stages. The most commonly recognised major forms of polymorphism are: Ad hoc polymorphism: defines a common interface for an arbitrary set of individually specified types. Parametric polymorphism: does not specify concrete types & instead uses abstract symbols that can substitute for any type. Subtyping (also called subtype polymorphism or inclusion polymorphism): when a name denotes instances of many different classes related by a common superclass.

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Ponzi Scheme

A Ponzi Scheme is a fraudulent scheme that involves paying existing investors in a nonexistent enterprise with the funds collected from new investors. A Ponzi scheme relies on a growing stream of new investors to create an illusion of profit. Some of the new money is used to pay earlier investors, making the scam look legitimate and highly profitable. Most of the money is pocketed by the scam's operator. The scam collapses when the supply of new investors slows and the supposed profits evaporate. A Ponzi scheme is similar to a pyramid scheme in that both use new investors' funds to pay earlier backers. A pyramid scheme usually relies on rewarding early participants to recruit more participants but collapses when the supply of potential participants dwindles.

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POS: Point of Sale

POS

A device allowing the use of payment cards at a physical (not virtual) point of sale. The payment information is captured either manually on paper vouchers or by electronic means.

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POS, Point of Sale

POST Method

Refers to a method used to send data to a server to create or update a specified resource using HTTP.

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Postcondition

In computer programming, a condition or predicate that must always be true just after the execution of some section of code or after an operation in a formal specification. Postconditions are sometimes tested using assertions within the code itself. Often, postconditions are simply included in the documentation of the affected section of code.

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Postman

An API platform for developers to design, build, test, and iterate their APIs. Postman can be downloaded here .

tech

Precision

In the context of search performance, precision is a measure of how relevant the retrieved results are to the given query. Specifically, search precision is defined as the ratio between the number of relevant results out of all of the results that were returned. A query with a high level of precision does not retrieve many items that are not applicable to the query.

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Precondition

In computer programming, a condition or predicate that must always be true just prior to the execution of some section of code or before an operation in a formal specification. If a precondition is violated, the effect of the section of code becomes undefined & thus may or may not carry out its intended work. Security problems can arise due to incorrect preconditions.

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Predicate Crime

Predicate crimes, also known as specified unlawful activities, refer to criminal offenses whose proceeds can potentially lead to prosecution for money laundering if they are involved in a transaction. Anti-money laundering laws typically encompass a broad range of such underlying crimes, which may include felonies, or all offenses listed in the criminal code of a jurisdiction. These crimes serve as the basis for money laundering charges, as the concealment or use of proceeds from predicate crimes through financial transactions is illegal.

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Prepaid Card

A payment instrument issued by a payment service provider that is preloaded with eMoney and can be used for purchases or withdrawals until the balance is depleted.

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Preprocessor

A preprocessor, or precompiler, is a program that processes its input data to produce output that is used as input in another program. The output is said to be a preprocessed form of the input data, which is often used by some subsequent programs like compilers. The amount and kind of processing done depends on the nature of the preprocessor; some preprocessors are only capable of performing relatively simple textual substitutions and macro expansions, while others have the power of full-fledged programming languages.

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preprocessor, precompiler

Principal

An entity that acts on its own behalf, with its own funds and at its own risk. In a debt service context, the face value of a bond or original amount for which it is issued, i.e., excluding interest payable.

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Private blockchain

A closely controlled network operated by consortia in which the data is confidential and is accessed only by trusted members. Private blockchains do not require a token.

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Private Key

A private key, also known as a secret key, is a variable in cryptography that is used with an algorithm to encrypt and decrypt data.

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Secret Key, Private Key

Procedural programming languages

A procedural programming language follows a series of functions to perform actions or solve a specific problem. In this low-level style, developers write procedures — or reusable blocks of code — that contain step-by-step instructions that manipulate data in a systematic way. It is commonly used in medium-sized applications & embedded systems where straightforward logic & control flow are essential. Examples: C C++ Java Pascal BASIC Use cases: Systems programming (i.e., operating systems, embedded systems, device drivers) High-performance applications Game development

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Processing

Information technology services and network communication services, such as authentication and authorisation, which enable the governance body of an electronic payment instrument scheme or arrangement, an operator of a payment system and/or participating payment service providers to provide services.

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Processor

A processor manages the card transaction process and acts as mediator between acquirer and issuer. In essence, it communicates data from a cardholder’s card to an acquirer and issuer. It checks details received from a cardholder’s card by forwarding them to its issuer for verification and carries out a series of anti-fraud measures against a transaction. Once a processor has received confirmation that card details are verified as approved or rejected, data is relayed back, via a payment gateway, to a merchant, who completes or declines a transaction.

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Production Environment

This is where software and other products are actually put into operation as their intended users intend to use them. Developers generally use this term to refer to the setting where end users will actually use the products. In a production environment, software programs and hardware are run in real-time, and it is where organisations and companies perform their daily operations. A staging environment is essentially a test sandbox or a close replica of a live production environment where developers can freely test software. Even though staging and production environments are very similar, they are completely separate.

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Properties

Refer to name value pairs that can be used in the API functionality.

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Prototype

In programming, a prototype is a foundational object that serves as a template for creating new objects. It is a core concept in prototype-based programming, a style of object-oriented programming where objects inherit properties and behaviour directly from other objects (prototypes) rather than through classes. Instead of defining classes and then instantiating objects, a base object (the prototype) is created and then it is cloned in order to create new objects, potentially modifying them as needed.

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Provisional settlement

The discharging of an obligation by means of a transfer of funds and/or a transfer of securities which is dependent on the fulfilment of certain conditions and can therefore be rescinded by one or more parties. See also final settlement .

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Prune & search

A method of solving optimisation problems suggested by Nimrod Megiddo in 1983. The basic idea of the method is a recursive procedure in which at each step the input size is reduced ('pruned') by a constant factor 0 < p < 1. As such, it is a form of decrease & conquer algorithm, where at each step the decrease is by a constant factor. Let n be the input size, T( n ) be the time complexity of the whole prune & search algorithm, & S( n ) be the time complexity of the pruning step. Then T( n ) obeys the following recurrence relation: T( n ) = S( n ) + T( n (1- p )). This resembles the recurrence for binary search but has a larger S( n ) term than the constant term of binary search. In prune & search algorithms S( n ) is typically at least linear (since the whole input must be processed). With this assumption, the recurrence has the solution T( n ) = O(S( n )). This can be seen either by applying the master theorem for divide & conquer recurrences or by observing that the times for the recursive subproblems decrease in a geometric series.

tech

prune and search, prune & search, prune-and-search, prune-&-search

PSD2: [Revised] Payment Services Directive

PSD,PSD2

The Revised Payment Services Directive (PSD2, Directive (EU) 2015/2366, which replaced the Payment Services Directive (PSD), Directive 2007/64/EC) is an EU Directive, administered by the European Commission (Directorate General Internal Market) to regulate payment services and payment service providers throughout the European Union (EU) and European Economic Area (EEA). The PSD's purpose was to increase pan-European competition and participation in the payments industry also from non-banks, and to provide for a level playing field by harmonising consumer protection and the rights and obligations of payment providers and users. The key objectives of the PSD2 directive are creating a more integrated European payments market, making payments more secure and protecting consumers.

fin, legal

PSD, PSD2, Revised Payment Services Directive, Payment Services Directive

PSO: Payment System Operator

PSO

A Payment System Operator (PSO) oversees and manages a payment system, ensuring its efficiency, reliability, security, and compliance with regulations. Examples include card networks (e.g., Visa), clearing houses (e.g., ACH), and real-time payment systems (e.g., Faster Payments Service or FPS).

fin

PSO, Payment System Operator

PSP: Payment Service Provider

PSP

Payment service providers are third parties that help merchants accept payments. Simply put, payment service providers enable merchants to accept credit and debit card payments (as well as direct debit, bank transfer, real-time bank transfer).

fin

PSP, Payment Service Provider, Merchant Service Provider

Public blockchain

A public blockchain is an open, decentralised network where anyone can access the ledger, run a node, and submit transactions without needing permission. The data is transparent and replicated across many independent computers making it tamper-evident and globally auditable. Public blockchains derive their security from decentralised consensus mechanisms – either directly (as in Layer 1 networks) or indirectly by anchoring to a decentralised Layer 1 (as in Layer 2 networks).

tech

Public Key Cryptography

Public key cryptography is a method of encrypting or signing data with two different keys and making one of the keys, the public key, available for anyone to use. The other key is known as the private key. Data encrypted with the public key can only be decrypted with the private key.

tech

Publish–subscribe pattern

In software architecture, the publish–subscribe pattern (pub/sub) is a messaging pattern in which message senders, called publishers, categorize messages into classes (or topics), and send them without needing to know which components will receive them. Message recipients, called subscribers, express interest in one or more classes and only receive messages in those classes, without needing to know the identity of the publishers. This pattern decouples the components that produce messages from those that consume them, and supports asynchronous, many-to-many communication. The publish–subscribe model is commonly contrasted with message queue-based and point-to-point messaging models, where producers send messages directly to consumers. Publish–subscribe is a sibling of the message queue paradigm, and is typically a component of larger message-oriented middleware systems. Many modern messaging frameworks and protocols, such as the Java Message Service (JMS), Apache Kafka, and MQTT, support both the pub/sub and queue-based models. This pattern provides greater network scalability and supports more dynamic topologies, but can make it harder to modify the publisher’s logic or the structure of the published data. Compared to synchronous patterns like RPC and point-to-point messaging, publish–subscribe provides the highest level of decoupling among architectural components. However, it can also lead to semantic or format coupling between publishers and subscribers, which may cause systems to become entangled or brittle over time.

tech

Pull technology

Pull coding or client pull is a style of network communication, where the initial request for data originates from the client, and then is responded to by the server. The reverse is known as push technology, where the server pushes data to clients.

tech

pull technology, pull coding, client pull

Push technology

Push technology, also known as server push, is a communication method where the communication is initiated by a server rather than a client. This approach is different from the 'pull' method where the communication is initiated by a client.

tech

push technology, push coding, server push

PUT Method

Refers to a method that is used to send data to a server to create or update a specified resource using HTTP. The difference between POST and PUT is that PUT requests are idempotent. That is, calling the same PUT request multiple times will always produce the same result. In contrast, calling a POST request repeatedly have side effects of creating the same resource multiple times.

tech

Pyramid Scheme

A pyramid scheme is a fraudulent and unsustainable investment pitch that relies on promising unrealistic returns from imaginary investments. The early investors actually get paid those big returns, which leads them to recommend the scheme to others. Investors' returns are paid out of the new money flowing in. Eventually, no new investors can be found and the pyramid collapses. A pyramid scheme funnels earnings from all recruited participants on lower levels of an organisation to participants on higher levels. Pyramid schemes rely on income from recruitment fees and not, as participants may believe, from the sale of actual goods or services with real value. Types of pyramid schemes: multi-level marketing pyramid scheme, chain emails, and Ponzi Schemes.

aml

Python

Python is a high-level, general-purpose programming language. Its design philosophy emphasises code readability with the use of significant indentation.

tech

QR (Quick Response) Code

QR

A machine-readable code consisting of an array of black and white squares (i.e., a type of two-dimensional matrix barcode), typically used for storing URLs or other information for reading by the camera on a smartphone. QR Code payments are payments that are made by scanning QR codes using a mobile device to initiate electronic money transfers.

tech, fin

QR Code, Quick Response Code

Query Engine

A query engine is responsible for processing queries and returning the requested data to the user. It receives SQL or other query language statements from the application, and converts them into a series of instructions that the database server can understand. The query engine also performs tasks such as parsing and optimising a query. ACID properties are usually implemented on the query engine of a database.

tech

Query Engine, Query Processor

Query String

The portion of a URL where data is passed to a web application and/or back-end database. The reason query strings are needed is that the HTTP protocol is stateless by design. For a website to be anything more than a brochure, stated needs to be maintained state (store data). There are a number of ways to do this: on web servers, use session state server-side, on clients use cookies. and in the URLs, store data via a query string.

tech

Queue

A queue is a linear data structure that follows the First In First Out (FIFO) principle, where elements are added at the rear and removed from the front. This organisation is crucial for various applications, as it ensures that the order of processing is maintained, making it ideal for scenarios like task scheduling and resource management.

tech

Queue management

Rules and procedures that determine the order in which transfer orders are released from the queue and processed – e.g., “first in, first out” (FIFO). Optimisation routines may or may not be used.

fin

Queuing

An arrangement whereby transfer orders are held in a queue by the sending participant or by the system until they can be processed in accordance with the rules of the system. In an RTGS system, payments are typically 'queued' because of a lack of funds or insufficient access to intraday credit. In netting systems, payments are 'queued' in order to prevent caps from being exceeded.

fin

R (Programming Language)

R is a programming language for statistical computing and data visualisation. It has been adopted in the fields of data mining, bioinformatics and data analysis/data science. The core R language is augmented by a large number of extension software packages, which contain reusable code, documentation, and sample data. R software is open-source and free software. It is written primarily in C, Fortran, and R itself. As an interpreted language, R has a native command line interface.

tech, stats

Range

The range is the difference between the highest and lowest values in a dataset (i.e., the largest number minus the smallest number). In other words, the range is a measure of how spread out the data is in a dataset.

stats

Ransomware

Ransomware is malware that locks and encrypts a victim's data, files, devices or systems, rendering them inaccessible and unusable until the attacker receives a ransom payment. Malware is the umbrella term for malicious software that enables unauthorised access to IT systems and devices.

tech

Rate Limit

Refers to the number of API calls an app or user can make within a given time period. If this limit is exceeded, the application or user may be throttled.

tech

RDBMS: Relational Database Management System

RDBMS

A Relational Database Management System (RDBMS) is a database management system based on the relational model introduced by Codd. In the relational model, data is represented in terms of tuples (i.e., rows). An RDBMS is used to manage a relational database. A relational database management system is database software that manages relational databases. In practice, the term RDBMS is often used interchangeably with relational database, though technically speaking, an RDBMS manages one or more relational database.

tech

RDBMS, Relational Database Management System

React

React is a free and open-source front-end JavaScript library that aims to make building user interfaces based on components more \"seamless\". React can be used to develop single-page, mobile, or server-rendered applications with frameworks like Next.js and Remix. Because React is only concerned with the user interface and rendering components to the DOM, React applications often rely on libraries for routing and other client-side functionality. A key advantage of React is that it only re-renders those parts of the page that have changed, avoiding unnecessary re-rendering of unchanged DOM elements.

tech

React, ReactJS, React.js

Read Operation

A read operation is generally defined as any operation that retrieves data without modification. Read operations should generally behave as if the underlying data were immutable. They may modify the retrieved data to change its format, filter it, or make other modifications, but the underlying data stored in the database system is not changed.

tech

Recall

In the context of search performance, recall is a measure of how many of the relevant items a query was able to retrieve. Recall is specifically defined as the ratio of the number of relevant results returned by a query compared to the total number of relevant entries in the dataset. A query with high recall retrieves a large number of the items that would be potentially relevant to a search query.

tech

Reconciliation

A procedure to verify that two sets of records issued by two different entities match.

fin

Record

A single entry in a database table is called a record or row. A record in a table represents set of related data. Basically, a record is a collection of fields.

tech

Row, Record

Recursion

Recursion is a method of solving a computational problem where the solution depends on solutions to smaller instances of the same problem. Recursion solves such recursive problems by using functions that call themselves from within their own code. The approach can be applied to many types of problems. Recursion is one of the central ideas of computer science. Repeatedly calling a function from within itself may cause the call stack to have a size equal to the sum of the input sizes of all involved calls. It follows that, for problems that can be solved easily by iteration, recursion is generally less efficient, and, for certain problems, algorithmic or compiler-optimisation techniques such as tail call optimisation may improve computational performance over a naive recursive implementation.

tech

Refactoring

Refactoring refers to a software maintenance activity where source code is modified to improve readability or improve its structure. Software is often refactored to bring it into conformance with a team's stated coding standards after its initial release. Any change that does not alter the behavior of software can be considered refactoring. Common refactoring activities are changing variable names, renaming methods, moving methods or whole classes and breaking large methods (or functions) into smaller ones.

tech

Refactoring

Refactoring is the process of restructuring and improving existing code without changing its external behaviour. It involves making code modifications to enhance readability, maintainability, and performance while preserving its functionality. Refactoring helps eliminate code smells, improve code organisation, and reduce technical debt.

tech

Reference counting

In computer science, reference counting is a programming technique of storing the number of references, pointers, or handles to a resource, such as an object, a block of memory, disk space & others. In garbage collection algorithms, reference counts may be used to deallocate objects that are no longer needed.

tech

Refund

In the field of direct debits, a claim made by a debtor for the reimbursement of debits effected from its account (with or without a specific reason being indicated by that debtor).

fin

REGEX: Regular Expression

REGEX

REGular EXpression is a search pattern that works with texts. Regex can be used in many programming languages. It is used to validate and search text in a flexible and short way with specific rules.

tech

REGEX, REGular EXpression

Regression

Regression is a statistical method that attempts to determine the strength and character of the relationship between a dependent variable and one or more independent variables. Regression is a statistical technique that relates a dependent variable to one or more independent variables. A regression model shows whether changes observed in the dependent variable are associated with changes in one or more of the independent variables. It does this by determining a best-fit line to see how the data is dispersed around this line. Regression helps economists and financial analysts with challenges ranging from asset valuation to making predictions. Several assumptions about the data and the model itself must hold for regression results to be properly interpreted.

stats

Reject

In the field of payments, a payment transaction whose normal execution is prevented by the payment service provider of either the payer or the payee prior to settlement.

fin

reject, rejection, rejected transaction

Relational Database

A relational database is a database model that organises data items according to predefined data structures known as tables. A table defines various columns with specific constraints and types and each record is added as a row in the table. The use of highly regular data structures provides relational database systems with many ways to combine the data held within various tables to answer individual queries. Relational databases take their name from algebraic relations which describes different operations that can be used to manipulate regular data. In most cases, relational databases use the SQL (Structured Query Language) to interact with the database system as it allows users to express complex queries in an ad-hoc manner.

tech

Remittance

Remittance refers to money that is sent from one party to another.

fin

Remittance Services

Remittance services are businesses that receive cash or other funds that they transfer through the banking system to another account. The account is held by an associated company in a foreign jurisdiction where the money is made available to the ultimate recipient.

fin

Remittance Services, Giro Houses, Casas de Cambio

Replication

Replication is a process of continually copying and updating data from one system to another system. In databases, this typically involves a server sharing a log of changes that other servers can read and apply to their own copies of the data. This allows changes to propagate between various servers without requiring each server to approve operations at the time of execution. Many types of replication exists that differ in terms of method of sharing, the architecture of which systems copy data from where, and what policies are in place to control the replication process. Replication is an important feature in many systems for maintaining data availability, distributing load, and providing copies of data for offline procedures like backups. Replication involves creating copies of the same database on multiple servers to distribute read traffic and improve availability. Why use replication? • Improves fault tolerance — if one server fails, others can serve requests. • Enhances read performance by distributing read queries across multiple replicas. • Provides data redundancy to avoid data loss.

tech

Report

A report is a formatted result of database queries, containing useful data for decision-making, problem solving, and analysis. Examples of reports include monthly statements, a list of users, a loan contract, etc. Reports may contain tables, pie charts, and images.

tech

Reserve Account

An account with the national central bank on which a counterparty's reserve holdings are maintained. The counterparties' settlement accounts with the national central banks may be used as reserve accounts.

fin

REST: Representational State Transfer

REST

Representational State Transfer is an application programming interface that conforms to the constraints of the REST architectural style and enables a quicker interaction between different RESTful web services. A stateless Web service must be able to read and modify its resources using a predefined set of operations and a textual representation.

tech

REST, Representational State Transfer

Restricted Electronic Money

A type of electronic money with limitations on its usage, such as only for specific merchants or services.

fin, aml, legal

Restricted Electronic Money, Restricted eMoney

RFID: Radio Frequency Identification

RFID

Radio frequency identification is an automatic identification method relying on storing and remotely retrieving data, using devices called RFID tags or transponders. An RFID tag is an object that can be applied to or incorporated into a product for the purposes of identification through the use of radio waves.

tech

RFID, Radio Frequency Identification

Risk

Or AML Risk Assessment, helps companies understand what conditions increase the chances of a customer's involvement in money laundering.

aml

Risk, AML Risk Assessment

Rolling Reserves

Rolling reserves are a financial buffer arrangement between payment processors and merchants that acts as a safeguard against chargebacks.

fin

RPC: Remote procedure call

RPC

In distributed computing, a remote procedure call (RPC) is an action in which a computer program causes a procedure (subroutine) to execute in a different address space of the current process (commonly on another computer on a shared computer network), which is written as if it were a normal (local) procedure call, without the programmer explicitly writing the details for the remote interaction. That is, the programmer writes essentially the same code whether the subroutine is local to the executing program, or remote. This is a form of server interaction (caller is client, executor is server), typically implemented via a request–response message passing system. In the object-oriented programming paradigm, RPCs are represented by remote method invocation (RMI). The RPC model implies a level of location transparency, namely that calling procedures are largely the same whether they are local or remote, but usually, they are not identical, so local calls can be distinguished from remote calls. Remote calls are usually orders of magnitude slower and less reliable than local calls, so distinguishing them is important. RPCs are a form of inter-process communication (IPC), in that different processes have different address spaces: if on the same host machine, they have distinct virtual address spaces, even though the physical address space is the same; while if they are on different hosts, the physical address space is also different. Many different (often incompatible) technologies have been used to implement the concept. Modern RPC frameworks, such as gRPC and Apache Thrift, enhance the basic RPC model by using efficient binary serialization (e.g., Protocol Buffers), HTTP/2 multiplexing, and built-in support for features such as authentication, load balancing, streaming, and error handling, making them well-suited for building scalable microservices and enabling language interoperability.

tech

RPC, remote procedure call

RPC: Remote Procedure Call

RPC

RPC, which stands for Remote Procedure Call, is a technique for building distributed systems that enables programs to call functions on other machines as if they were local. In an RPC system, a client program sends a request to a remote server program to perform a specific procedure, passing any necessary input data. The server then processes the request and returns a response with any output data. The client program can then continue its execution based on the response it receives. The RPC protocol abstracts the details of the network communication between the client and server, allowing them to communicate as if they were both on the same machine. The protocol can be implemented using a variety of transport protocols, such as TCP or UDP, and can use different encoding schemes to represent the data being transmitted, such as JSON or XML. One of the main advantages of RPC is that it allows programs to work together without knowing the details of each other's implementation. This makes it easier to build complex distributed systems, as each team can focus on its own program's functionality.

tech

RPC, Remote Procedure Call

RSA: Rivest-Shamir-Adleman

RSA

Rivest-Shamir-Adleman is a public-key cryptosystem that is widely used for secure data transmission. It is also one of the oldest. In a public-key cryptosystem, the encryption key is public and distinct from the decryption key, which is kept secret (private). An RSA user creates and publishes a public key based on two large prime numbers, along with an auxiliary value. The prime numbers are kept secret. Messages can be encrypted by anyone, via the public key, but can only be decoded by someone who knows the prime numbers. It is a relatively slow algorithm.

tech

RSA Public Keys, Rivest-Shamir-Adleman, RSA

RTGS: Real-Time Gross Settlement

RTGS

A settlement system in which processing and settlement take place on a transaction-by-transaction basis in real time.

fin

RTGS, Real Time Gross Settlement, Real-Time Gross Settlement

Rust

Rust is a general-purpose programming language emphasising performance, type safety, and concurrency. It enforces memory safety, meaning that all references point to valid memory. It does so without a conventional garbage collector; instead, memory safety errors and data races are prevented by the \"borrow checker\", which tracks the object lifetime of references at compile time. Rust does not enforce a programming paradigm, but was influenced by ideas from functional programming, including immutability, higher-order functions, algebraic data types, and pattern matching. It also supports object-oriented programming via structs, enums, traits, and methods. It is popular for systems programming.

tech

RWA: Real-World Assets

RWA

Real-world assets (RWA) are items with value in the real world, including bonds, equities, money market funds, real estate, commodities, art, or other intellectual property. In the digital asset space, these assets can be represented as tokens – through tokenisation – on a blockchain, enabling secure, transparent and efficient trading, and broader access to investment opportunities.

tech, fin

RWA, Real-World Assets