The visual display (vi) editor is an interactive command line text editor that is used to display and edit the contents of a file. All editing in the vi editor is done in a buffer (a special storage area in memory); therefore, changes can either be written to a disk or discarded.

Users that are working their way up to system administrator need to know how to use the visual display (vi) editor to edit crucial system files from the command line.

Fluency in vi will come in very handy if the windowing system is unavailable and all you have at your disposal are the command line tools. That is why this module describes how to use the visual display (vi) editor to create and modify text files.