NEW YORK (CNN) -- When you watch a baseball game or a golf tournament or an auto race on TV, you've no doubt noticed commercial logos finding their way into the camera shots.

But what you may not realize is that people actually participating in the game or the tournament or the race don't see those logos. In real life, these ads don't exist. Rather, they are being electronically inserted into your television program, unbeknown to you.

Until now, that is. Join CNN's Jeanne Moos as she gets the low down on the technology that makes these virtual ads possible.

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