Use a Single Editor Well
We think it is better to know one editor very well, and use it for all editing tasks: code, documentation, memos, system administration, and so on. Without a single editor, you face a potential modern day Babel of confusion. You may have to use the built-in editor in each language's IDE for coding, and an all-in-one office product for documentation, and maybe a different built-in editor for sending e-mail. Even the keystrokes you use to edit command lines in the shell may be different. It is difficult to be proficient in any of these environments if you have a different set of editing conventions and commands in each.
But you need to be proficient. Simply typing linearly and using a mouse to cut and paste is not enough.
Choose an editor, know it thoroughly, and use it for all editing tasks. If you use a single editor (or set of keybindings) across all text editing activities, you don't have to stop and think to accomplish text manipulation: the necessary keystrokes will be a reflex. The editor will be an extension of your hand; the keys will sing as they slice their way through text and thought. That's our goal.
Make sure that the editor you choose is available on all platforms you use. Emacs, vi, CRiSP, Brief, and others are available across multiple platforms, often in both GUI and non-GUI (text screen) versions.