vim --version  shows the vim version and its enabled complements
vim -g         starts vim in graphical IDE

u           Undo last action
dd          Remove current line
d5d         Remove five lines
:e!         Reread the file and override done changes

:<n_line>         Go to that num of line
/<word>           Search that word. n key will look for the next one.
gg                Move to the beginning of the line

set number        Show line numbers

:tabe file      To open a file in a tab
gT and gt       To change between tabs
:qa             To close all tabs at once

:!command       Run system command from vim
:!!             Run the selected text as system command