procesor technologies and OS technologies

Yes both have relations.. U can install a 32 bit operating system only in a processor made of 32 bit instruction set.. 64 bit instruction set processor supports both x86 and x64 OS... 64 bit OS has more advanced graphics and extreme level of working.. 32 bit is highly enough for home usage.. Sometime some 32 bit processor might accept a 64 bit OS

Well, let us try to talk about it in a nutshell: a bit is a short for binary digit, and it is basically related to how a computer stores and make references to data, memory, etc. A bit can have a value of 0 or 1. A stream of those codes makes a binary code, like: 011110010 (8b), or 0111010100101011 (16b) and so on. An 8b code can represent codes from 0 to 255, and a 16b code may represent codes from 0 to 4.294.967.295 (look for binary code in order to know more about it). A 32b processor can handle codes up to 32b, while a 64b can handle up to 64b codes. The OS must match the capcity of the processor if it wants to be able to use it to its fullest. Day to day aplications does not have any complex information that requires 64b to work, so, you do not really need to have a 64b PC on your home, only if you intend on handling large databases or complex video aplications to run smoothly. Let us say: if you use your computer only to write texts and surf the web, having a 64b CPU will not make you computer experience faster. But, if you'd like to play some high advanced graphics game, a 64b PC would help to improve your perfomance. Hope it helped you a little.