vim / vi is a powerful text editor with a small footprint. It’s been used for years and is a useful tool to know.
Even if you don’t want to use vim as your primary editor, it’s beneficial to know so that when you are logged into an external server, you can still manipulate files with ease using vim.
Run: vim vimtut
and go through the file and try those commands
SPF13 VIM - My favorite one
Sublime-style VIM
# type this into your terminal
vimtutor
Vimium for Chrome
VIM Cheatsheet
OpenVIM tutorial
Vintage - VIM mode for sublime text 2
VIM mode for sublime text 3
VIM mode for Atom editor
Vi keybinding list