What is the thinkpad-keys application?

[Marvin Raaijmakers]

I have Ubuntu installed on my ThinkPad T60 and I noticed that an
application called thinkpad-keys makes the volume up/down/mute keys
work. After running this application, there is a new event device
in /dev/input/ (does this userspace application create a device?).
So I am asking myself what the thinkpad-keys application actually is and
does. Google couldn't give me the answer (or is it tpb?
http://www.nongnu.org/tpb/).
So I think someone on this list will be able to answer my question.

- Marvin Raaijmakers