To use a computer program to translate source code written in a particular programming language into computer-readable machine code that can be executed.
To translate all the source code of a program from a high-level language into object code prior to execution of the program. Object code is executable machine code or a variation of machine code. More generally, compiling is sometimes used to describe translating any high-level symbolic description into a lower-level symbolic or machine-readable format. A program that performs this task is known as a compiler. See also compiler (definition 2), compile time, high-level language, machine code, source code. Compare interpret.