It evaluates the arguments to the command as bash commands. So if you save the file as foo.sh and add it to your PATH. You could run: $ foo.sh 'date ; ls

It evaluates the arguments to the command as bash commands. So if you save the file as foo.sh and add it to your PATH. You could run: $ foo.sh 'date ; ls ; foo=bar ; echo "Hello $foo"' Or really anything you'd like as the argument is treated as a bash script. NOTE: The original comment had the #! of the shebang backwards (as !#) due to a typo.