When logging out of a UNIX system, the .logout file is executed. This file is usually very short, and contains commands users want to execute upon leaving UNIX. The most popular is the clear command, which clears the screen.
Another popular command (on Suns) is to invoke fortune, which prints a ``saying" as a goodbye message. This is done by adding the following line after the clear statement:
if (-e /usr/games/fortune) /usr/games/fortune -a