Linux Text Editors

The Vi Editor

The Vi editor comes with every version of Linux or Unix. Using vi is similar to using other editors in that you can see your file on the screen (this is not the case with a line editor, for example), move from point to point in the file, and make changes. But that's where the similarities end. Cryptic commands, a frustrating user interface, and the absence of prompts can all drive you up a wall. Still, if you focus on a few basics, you'll get the job done.

Command and Input Mode
When using Vi editor, you're always in either Command or Input mode. Unfortunately there's no clue as to which mode is currently active. In Command mode, you can move the cursor, search for characters, and delete existing text. But to enter or edit new text, you have to switch to Input mode. When you start vi, you're in Command mode. To enter Input mode, type the letter a (lowercase only) to signal that you want to add text after the cursor position. Press esc to switch back to Command mode at any time. Here's how to create a file from scratch using vi.
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The Emacs Editor

The Emacs editor is a lot easier to use than vi. There are no silly modes to trip you up when you want to enter text, you just position the cursor and type. It also has built-in help. But while Emacs is a vast improvement over vi, you'll still have to remember quite a few commands to be productive, and you'll probably get a little lost. If vi is a relic of the sixties, Emacs sports the cutting-edge technology of the early eighties. If you get into a situation where Emacs seems to be stuck, or if you don't know what to do, press ctrl-G and things will return to normal. (The ctrl-G key cancels the current operation in Emacs.)
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The Pico Editor

Pico, short for Pine Composer, started life as the built-in editor for the Pine email program. Lots of people use Pico as a text editor because they also use the friendly Pine program for email. The Pico text editor doesn't have a lot of fancy features, but it's a welcome alternative to the vi or Emacs editors because learning it is quick and easy. Cursor movement and text entry are straightforward, and--best of all--you don't have to learn any arcane commands: all commands are listed in a handy menu at the bottom of the screen.
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