Beginning version 7, Vim started to introduce its auto-complete feature. By default it works by being able to auto-complete words that already existed in the file being edited. If enabled, it can also auto-complete syntax for various programming languages.

To use the Vim auto-complete feature, just hit Ctrl + n while in insert mode, and you’ll get a list of word suggestions as in the following example;

To make the list cycle backwards, hit Ctrl + p. You can also use the arrow keys to move up and down the list.