1) vi . profile
shows alias for commands, you can set the new ones.
2) esc =
displays the file and folders in a numbered fashion.
3) esc – or esc k ( esc n does the same thing reversely)
shows the previous commands
4) cd esc \ [type something]
completes the word starting with your typed ones.
5) cd – ( switches between your last folder path and current folder path)
6) export [someName] = someValue
creates an environment variable and sets it a value.