What is your Operating System (OS) that you used for?, Tell me why??  

i use apple macs

Windows XP Professional. Because this is already installed in this computer when this was sent by our head office. But I really love this OS than Vista or others.

i use windows vista ultimate edition..its really error free..much better than XP..althought i do have sometimes trouble running old MS DOS applications ..but othr than tht vista seem pretty good than the operating systems released so far

i am using windows xp professional, because its more reliable, faster than the windows vista...i put more emphasis on speed and reliability rather than attractive features..other than win xp i like linux.

I am using windows xp pro in my computers.As I am familiar with only XP, I find this is the best suited to me. Few months back, I tried with the windows vista and found much difficult with that..Responding to the numerous windows itself was a great task for me and then immediately I formatted the system and installed the windows xp again. I feel this is the only OS , which is very much user friendly..But this is the only OS ,the most of the virus are targeting..

I am using 2 os.one is windows xp,the others is windows vista.
they are all very their benefits.
the windows vista s' interface is very nice than the windows xp,but it needs our room large.
I used windows xp for 5 years ago. so I am very familiar with it.