It dates back to a long time ago, in a land not so far away, but way out west somewhere....
This is to help installers and programmers when trying to do an install or troubleshoot what is occurring.
For a standard large scale blasthole drill with tracks, the front of the drill is where the cables would come into it if
it were electric. So, where the drill mast is located is considered the back of the drill.
On a drill that is mounted on a truck body, so has wheels, the drivers cab will be at the front like a normal vehicle
with the drill mast mounted on the back.
For air-track drills (smaller drill - typically on tracks) that has a mast that moves in any direction, the mast is
still considered the back of the drill.