Cause the shell to exit.
Syntax exit [n] Key n Set the exit status to n
If n is omitted, the exit status is that of the last command executed. A trap on EXIT is executed before the shell terminates.
exit is a bash built in command.
“An exit strategy is a means of escaping one's current situation, typically an unfavourable situation” - Wikipedia
Related:
screen - Multiplex terminal, run remote shells via ssh
shutdown - Shutdown or restart OS X