thumbdrive

i want to load OS(DOS or Windows) on thumb drive...so isit possible?

Yes, if the computer's BIOS supports booting off the USB port.

I've seen it done.

can u tell me the procedure pleas... i want to install windows..

It's no different than installing an OS on a hard drive.

Just change the boot order in the BIOS so the USB drive is the first to boot.