what's difference between SID GUID and CLSID

Can folks please explain the difference between CLSID, GUID and SID?

Isn't the CLSID also called the class ID? Still what is the difference between it and GUID?

Does IDBlaster affect the SID? Again, correct me if I am wrong but the SID is a unique number for objects in the domain (2000/2003 Server) and changing these numbers I'd guess would prevent object/user identification and mess up object access.
Thank you.

[Prince_Serendip]

Don't know about answering your last question except to say that I have used IDBlaster for over a year with no problems whatsoever.

http://www.w3.org/Addressing/clsid-scheme

http://sources.redhat.com/sid/

http://en.wikipedia.org/wiki/Globally_Unique_Identifier

Hope the above definitions are of some help to you.

Best regards

I know this is a late reply, forgive me. Microsoft allocates a unique "SID" to every operating system it sells, and uses this root ID to validate the genuine article. When a user pirates a copy to someone else, it can be known, because every disk, and every OEM is stamped with this Unique #. When you go to The update center at Microsoft, this id is chronicled and dated. That is why a history of your downloads is always accurate, no matter what other id you change. However, there is a very bright man, who developed a Free software, calles "Newsid", Mark Russinovitch, and this effectively changes your SID. This software may be found at www.sysinternals.com,
I hope this sheds a little more light on the issue.
Slikk