Description of iPod generations?

I think that Apple was originally saying that the new iPods were the gen 2 iPods, and all of the ones perviously sold were gen 1 iPods, but when they officially released them they were advertised as gen 3 iPods.

So what are the descriptions of each generation. I've heard them described two ways. Iuess the popular one is, gen 1's have the scrollwheel, gen 2's have the touchwheel, and gen 3's have the new button locations. But, I have also heard that the gen 1's are the original 5gb, gen 2's are the 10gb scrollwheels and the all of the touchpad ones, and gen 3's have the new button locations.

I guess I would go with the first one, but I suppose that some may go with the second one.

Bill McNair

1)Scrollwheel
2)Touchwheel
3)Touchbuttons

Now there are anomalies. Such as the rereleased 5GB, which included the 2G style headphones and box, but had a scrollwheel and no firewire port cover.