Some commonly used commands, the black part of the command is more important:
oEnter the editing mode,
after editing,
press the ESC key to switch to the command mode, and then enter the following commands to perform corresponding operations:
:w save the file without exiting vi editor
:w! Forced to save without exiting vi editor
:w file Save the modification to file without exiting vi editing
:wq save the file and exit vi editor
:wq! Force to save the file and exit vi editor
:q do not save the file and quit vi editing
:q! Do not save the file and force quit vi editing
:e! Discard all modifications and start editing from the last saved file