procedure

In computing, a small part of a computer program that performs a specific task, such as clearing the screen or sorting a file. A procedural language, such as BASIC, is one in which the programmer describes a task in terms of how it is to be done, as opposed to a declarative language, such as PROLOG, in which it is described in terms of the required result. See programming.

Careful use of procedures is an element of structured programming. In some programming languages there is an overlap between procedures, functions, and subroutines.