Learn about and revise programming concepts with this BBC Bitesize Computer Science AQA study guide.

In programming each variable stores a certain value of a particular type. For example, data types can be a number, string (text), a boolean type, data, list, etc.

The variable in the RANGE statement, the ID variables, and the BY variables are available for the model program to examine, but their values should not be changed by the program.

Variables in programming languages often reflect the language's memory model. However, in Inference, there is no concept of a memory model. Inference is a language for defining formal specifications.