ok, like he said... you can use it on ONE desktop and ONE laptop. You also have the ability for a one time transfer to a different owner, AND you can transfer it to another one of your PC's as long as its REMOVED from your original. As in, only ONE PC, and ONE laptop but is transferable as long as you limit it to just one desktop and one laptop. Now this is for the retail version. If you purchase from, say.. Gateway the rules are different and it MUST stay with the ORIGINAL system, no transfers from system to system and no transfers from person to person and can only be on one system, no laptop xtra with that. Now this maybe different depending on the company and liscensing type, but for just a standard consumer, this is usually the norm.