What is the in a .vimrc file?

Question

I see in many .vimrc files, and I am wondering what does it mean?

What is it used for?

Just a general overview of

Answer 1

The "Leader key" is a way of extending the power of VIM's shortcuts by using sequences of keys to perform a command. The default leader key is backslash. Therefore, if you have a map of Q, you can perform that action by typing \Q.