Programming languages are the primary tools for creating software. As of 2002, hundreds exist, some more used than others, and each claiming to be the best. In contrast, in the days when computers were being developed there was just one language—machine language.

The concept of language generations, sometimes called levels, is closely connected to the advances in technology that brought about computer generations. The four generations of languages are machine language, assembly language, high-level language, and very high-level language.

First Generation: Machine Language

Programming of the first stored-program computer systems was performed in machine language. This is the lowest level of programming language. All the commands and data values are given in ones and zeros, corresponding to the "on" and "off" electrical states in a computer.

In the 1950s each computer had its own native language, and programmers had primitive systems for combining numbers...