About vi

vi was derived from a very old Unix text editors like ed and ex which were a line editors designed to work on teleprinters, rather than display terminals. The name "vi" comes from the ex command visual, which switches the ex line editor to visual mode. vi is visual editor - visual editors are ones that let you see the document that you are editing as you edit it. Non-visual editors examples: sed, ex, ed, and edlin.

The original code for vi was written by Bill Joy at UCB, in 1976, as part of the BSD distribution of Unix. It become part of the Single Unix Specification Standard and POSIX, demanding every conforming Unix distribution to include it.

vi is still widely used by users of the Unix family of operating systems. The traditional vi is a rather small program (the binary size is approximately 200 kBytes.