Learn About RGB
What is RGB!? RGB is referring to Red Green and Blue (and also sync), and when using this analog method of input you get a more vibrant and sharp image than just using composite. Composite is sometimes referred to as "AV hookup". It's a yellow rca connector. Composite is the most common way people hook up their only consoles to crt tvs, but it's also one of the worst as far as quality goes.

Check out this image, it's an example of composite input on a tv.

And here's that same image, on the same tv, but the tv has been modified to accept RGB. Notice how much sharper the image is, and how much more color accurate the colors are!

Composite

RGB

Composite

RGB

Composite

RGB