双石

A programming language is a formal constructed language designed to communicate instructions to a machine, particularly a computer. Programming languages can be used to create programs to control the behavior of a machine or to express algorithms. (Source:wikipedia)

Computers understand languages by manipulation of binary bits. This is called machine language. Humans often use  High-level language to program. High-level language is based on assembly language ,which is based on machine language. High-level language is closer to natural human language. It uses a compiler to make it understood.