heyfrenz i just need a proper explanation of why is unix a 32-bit operating system??....a proper answer with proper explanation....

It's not. I have used 16 bit versions of unix. Now it's a split between 32 and 64 bit versions of unix. I believe that there was once a 24 bit version, but I don't remember for sure. Can anyone confirm? Any others?

Considering only the 32 bit versions of unix, the primary reason that they were a 32 bit implementation was that they were running on a 32 bit CPU. A few people run 32 bit unix on 64 bit CPU's. At first, this was because the manufacturer had not yet finished the 64 bit os and the 32 bit was the only choice. Some people continue to 32 bit versions of unix on a 64 bit cpu. There is no easy explanation for this. Some people still use 80 column cards too.

Actually I have a reason for running 32 bit unix on 64 bit processors - software compatility. We have several old apps which the original software provider is now out of business. We need to keep them running, but there hasn't been a new version in years so we're stuck running the 32 bit version.

Also, working in a medical company means FDA regulations require we keep systems used in developing products running for up to 10 years after the product is approved. We still have OS/2 production servers first built in the mid 90's that we have to keep running still, along with some old SunOS and other old stuff. And some of that ancient equipment and software will have to be kept going for a long time yet before we're allowed to retire it.

Friends,
I am new to computer field, what is a 32 bit operating system?
How it is different from 16 bit or 64 bit OS.

It is compiled for 32-bit processors.

Thanks eugrus!
Can you or anyone elaborate, on 32-bit/64-bit OS.
As a programmer, how is it going to make any difference?
If I develop a software on 64 bit OS, will it run on 32 bit OS? Do I really need to worry about this while developing any application?

Please let me know if I am deviating the topic, I can open a new thread.

Thanks in advance.