Resources

Glossary

Plain-language definitions of the terms used across this website.

A

API: Application programming interface: a defined way for two software systems, such as an operator platform and a game, to exchange information.

B2B: Business to business: products and services sold from one company to another rather than to the public.

Gambling Commission: The regulator of gambling in Great Britain. It publishes a public register of the businesses it licenses.
Game launch: The process by which an operator platform opens a game for a player and passes the session information the game needs.
Game round: A single play of a game from stake to result.

Hit frequency: How often a game round returns anything at all, expressed as a percentage or ratio of rounds. A return can be smaller than the stake.

Independent test laboratory: An independent organisation that tests game software and random number generators against technical standards before release.

Licensed operator: A company that holds the gambling licence or licences needed to offer games to players in the markets it serves. Rectangle Games supplies licensed operators.

Maximum win: The largest return a single game round can produce, usually expressed as a multiple of the stake. It is a technical limit of the game, not an expected outcome.
Multiplier: A value by which a return is multiplied, as defined by the rules of each game.

Payline: A line across the reels on which matching symbols produce a return.
Production: The live environment in which games are used by an operator's players.

Remote gambling software licence: A Gambling Commission licence that authorises the manufacture, supply, installation and adaptation of gambling software by remote communication.
RNG (random number generator): Software that produces unpredictable results so that each game round is independent of the last. In regulated markets, random number generators must be tested in line with that market’s technical standards and testing rules before release.
RTP (return to player): The percentage of all money staked on a game that is returned to players over a very long period of play. A game with an RTP of 97% is designed to return, on average, 97 units for every 100 staked over the long run. It is a statistical average, not a prediction of any single session.

Scatter: A symbol that produces a result wherever it lands on the reels, rather than along a payline.
Software supplier: A company that makes and supplies gambling software to operators. Software suppliers do not offer gambling to players themselves.
Staging environment: A test environment that mirrors production, where an integration is built and checked before it goes live.
Stake: The amount a player pays to play a game round.

Volatility: Describes how the returns of a game are spread. Low-volatility games tend to return smaller amounts more often; high-volatility games tend to return larger amounts less often. Two games can share the same RTP and still feel very different to play.

Wallet: The part of an integration that handles player balances and transactions between an operator's platform and a game.
Wild: A symbol that can substitute for other symbols to complete a winning combination, subject to the rules of each game.

Definitions are general explanations. The rules of each game and the terms of each regulator apply. See also math and fairness.