What is Vim?
Vim is an advanced text editor that provides a more complete feature set than Vi, a Unix text editor. Vim is a highly configurable text editor built to enable efficient text editing. It is an improved version of the Vi editor distributed with most UNIX systems. Vim is often referred to as a programmer's editor, and so useful for programming that many consider it an IDE. Vim can be used for all kinds of text editing, like composing emails and editing configuration files. Vim isn't a word processor. Although it can display text with various forms of highlighting and formatting, it isn't there to provide WYSIWYG editing of typeset documents. Vim is distributed freely. Its license is GPL-compatible.