pico style editor are small, easy to use and have been around for ever. Almost every unix based system has one.
vi text editors are designed for minimalism, but to remain very powerful. They are hard to learn because there are no menus, all operations are done with keystrokes or commands. The first time you use vim, you will most likely not be able to do anything and if you type like normal, it will seem like its gone crazy. Once you get used to vim's interface, you can quickly edit files and preform many complex tasks. vi is capable of doing anything you would expect of an advanced editor. vi is recommended for people who like to do everything command line.
emacs(gui and console)Edit
Emacs is a very powerful editor, and is easy to use. It is menu based and unlike vi, is designed to be Big. It can be your email client, web browser, IRC client, and almost anything else. The editor allone is very powerful and can do anything you would expect and more.
- nedit: lightweight gui editor
- gedit: Gnome editor, very simple
- emacs: Very popular editor
- gvim: gui vim, is easier to use because it has menus if you don't know the keystrokes or commands
There are a lot
- HEX editors