In VIM the productivity is boosted with three independent modes.
- Command mode: all keystrokes are interpreted as commands. You return to this mode pressing Esc.
- Insert mode: most keystrokes are inserted as text (leaving out those with modifier keys). You enter with i, a, I or A.
- Visual mode: helps to visually select some text. You enter with v, V.
For a small intro to VIM see this great tutorial.
Here you can find a nice .vimrc