BleepingComputer.com: How do I use two monitors on a single pc?

So, we've all seen it, but I'm curious how does it actually work? I have two monitors and wouldn't mind mounting one on the wall to have the internet open at all times when playing a game, but I am curious what does it take in order to have two monitors that show two different things for the same pc? Better yet, is it even possible? I knew some kid back in Everquest who played with 6 monitors for each of his 6 characters but I was so young that i didnt think to ask him questions of how it worked. So... Here are some of my questions.

How do you get the mouse to each monitor?
How do you control which monitor the keyboard will be typing on/going to or will it do all of them?

I guess if you guys confirm if this is even possible in the first place It will raise a few more questions, but for now I'll leave it at that!

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