Why system32 is called so ?(not system 333)..And what is it ?

Answer 1

I believe it has to do with data transfer. 8 bits (8 switches each either on or off) make one byte of data. One byte would be equivalent to one letter, digit etc. 32 bits would be four bytes. In this case it would be referring to the fact that 32 bits, or 4 bytes are transferred simultaneously. Think of it as a four lane highway, in which four vehicles can travel side by side.
The next level would be 64.

Answer 2

Sparbles is right. I'll just add that as 8 bit was the basic unit of everything on the early PCs. We're now using 32 or 64 bit processors, meaning thats now the basic unit. Everything your processor does is usually in 32 bit functions... 32 bit memory addressing. Windows 2000 is a 32 bit operating system regardless of what newer processor you might have. That's where system32 comes in. However, if you switch to vista(or XP I think) and have a 64 bit processor I believe that is supposed to mean twice the performance at the same number of gigahertz, Because it can do twice as much per instruction. It would never be 33 because computers like to do things in even multiples of 2. Binary math works like 1 2 4 8 16 32 64 128...