Source code
In computer programming, 'source code' is a text file version of a computer program or software that contains instructions that the computer follows to do something. Source code is written in a programming language which a human can read and change. A large program may contain many different source code files that all work together. These days most source code is 'compiled' when it is finished. This translates the code into assembly language or machine language which is much faster and easier for the computer to read, but hard for a human to read.