Save exit/quit commands saves exit and quit commands in the command history.

Save consecutive duplicate commands saves consecutive executions of the same statement in the command history.

With this option selected, if you run magic(5) two times in a row, both entries for magic(5) remain in the command history.

With this option cleared, the command history retains only one entry for magic(5). If you then run magic(10), the command history retains both entries.

Save history file on quit saves the command history file only when you end a MATLAB session. If the session ends abnormally, such as due to a power failure, then the MATLAB does not save the history file for that session.

Save after n commands saves the command history file after MATLAB adds n statements to it. Use this option instead of Save history file on quit if you do not want to risk losing entries to the saved history because of an abnormal termination.

Don't save history file is useful when multiple users share the same machine. It prevents each user from viewing the statements others have run.

Any entries already in the command history remain unless you first follow the instructions in Delete Entries from the Command History Window.