One is a bar room, and one is a Barooooooooooooom!
A walrus has at least two valid points.
The second letter.
Because he never left the pub.
Said the man in the pub to the bear. First heard this joke told by Eddie Izzard.
One is a bar room, and the other is a *BARROOM!*
One is a bar-room and the other is a BAROOOM!