From an article in IGN:

Nintendo’s sensor does serve an important purpose. The bar itself is really nothing more than a shell for two infrared sources - one on each end. It’s the same technology commonly found in a variety of electronic devices such as television remotes. The infrared sources located in the sensor bar emit lights that can’t be seen by the naked eye, but are nevertheless plainly visible by the Wii remote, whose tip features a very basic camera that can read IR data. The Wii remote uses the IR sources as a calibration point, setting the left and right boundaries. It’s very simple tech, but it works. The Wii remote doesn’t see your television when you point at it - it sees the IR sources on the sensor bar and orients itself based on those points.

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Tags: Nintendo, Wi, sensor bar

    

Glad I knew that, wow, i feel smarter!

it just lets wii-mote know were the screen is a kind of back up to the wiimotes sencers nothing more nothing less you can even use candels or flashing lights insted

that’s why it’s important to place the sensorbar n the middle of the tv-screen!

I got nothing so, WII RULES!!!

it wont matter where you put the console because when you first turn on the Wii it calibrates it to where your remote already is, that y it made sense to put a standby function so the controller can put the console in and out of standby. if u start the console with the controller to the right of the tv the Wii will set that as the center of the screen, that might get a little irritating. but i guess it will take a while to get used to.