Does anyone knows how TeamViewer gets screen capturing?

I need some game capturing advice?

• Ok, this might be a little confusing, but hopefully someone will understand what I'm talking about. What I am trying to do is record my monitor and xbox (not at the same time) via my monitor. I need to know what software (Free for now, might buy something if it gets entertaining) I should use to capture my monitor, and how I can have my xbox display on my monitor. I can currently play my monitor on my tv screen via a cable that hooks from it to my monitor (No idea what its called), however, I don't know how to reverse it. If anyone knows what I should do, or has any advice at all, I would greatly appreciate it.

• Answer:

  I use something called Camtasia Studio. I've only used it a few times but it's great. You can save your movie in any format for any device and you can edit it using this program as well. I recommend it! Take a look. http://www.techsmith.com/camtasia.asp