Urgent help with Counter-Strike Source

I have just purchased Counter-Strike Source and am really eager to play it. Only the thing is,I am having my PCcompletely reformatted soonand am worried that once I have done that, I won't be able to play the game anymore because Steam won't be on my computer.You can obviously only have one CD Key, and so once I enter that, I won't be able to use it again (will I?).

So can anyonetell me if it safe to install and play the game and that it will work fine after thereformatting?
Please keep in mind I am a complete and utter noob in terms of Counter-Strike and Steam and all that.

Don't worry about it. Steam games are based on the account and not computer. So all you need to do is download steam, log in and the game will automatically start download and installing again on it's own. No need to worry about CD Keys.Cdscottie

That's awesome to know, thanks a lot! You've saved me the trouble of having to contact Steam...