FaceTime gives you the ability to make high quality video calls over the Internet, much in the same way that Skype does.
In comparison, both apps are actually quite similar, but FaceTime is more tightly integrated into the Mac OS X, iPhone, iPad and iPod and the interface is much nicer and less fussy.
How to make a FaceTime call:
To get started, just launch FaceTime from either your Applications folder or your Dock, and the FaceTime window appear.
FaceTime uses your Address Book, so if you have friends or family with iPhone, iPad, iPod touches, or Macs, just click their e-mail address or phone number to initiate a video call.
The person you’re calling (in this case my son) will Appear in the main window and you can see yourself down in the left corner