The aird daemon handles Apple IR receiver button events.  If your system
has an USB Apple IR receiver, most likely you'll also have an Apple
Remote.  An Apple remote has six (6) buttons: Volume up, Volume down,
Play/Pause, Forward, Backward and Menu.  For each button you can assign a
command to execute.

Apple IR receiver modules are found on:

           o   MacBook (any generation)
           o   MacBook Pro (any generation)
           o   Intel iMac
           o   Intel MacMini

WWW: https://wiki.freebsd.org/AppleMacbook