Microsoft 'Utilities'

I noticed when I run HiJack This to check for
unwanted items, two M.S. 'utilities' always show up:

a.) Windows Genuine Advantage Validation Tool
and
b.) Microsoft PID Sniffer

I've since found out for what the Validation Tool is used.

Does anyone have any idea what the PID Sniffer is and
for what it's used (...and for what 'PID' is an acronym)?

Can someone please tell me (if you know):

1.) What the PID Sniffer is and for what it's used
(...and for what 'PID' is an acronym)?
2.) Do I need it for anything (i.e. Windows or
Office Update -- or something else)?
3.) How would it have gotten on my system
(or does M.S. just automatically install it)?
4.) If I DON'T need it, how would I remove it?
(I don't see it in the Add/Remove Panel).

Thanks in advance for your help - I appreciate it,

Mike___________