Ghost controlling computer?

hi, today i went to my friends house, when i went over to his computer, it was on, and the mouse cursor was moving but the mouse wasn't, it looked like the computer was hacked, i rushed to my friend and asked him about the computer but he says that his brother is doing that on his brothers computer to fix some internet settings.
Do any of you know how to do this? or what this is called? i would really like to know so my cousin can fix my computer without coming over to my house.

thank you very much.

google up Windows 7 Remote Assistance dude
theres also 3rd party apps that will do it too..

LogMeIn
TeamViewer
VLC
Remote Desktop
GoToMyPC

These are the top tools used for remote help, but I'm sure there are others.

thank you