difference.....

example:

What are the differences between 1G Original, 2G Original, 3G, 4G iPods and iPod mini?

1st Generation iPods (Classic, Original, Gen 1, G1, 1G)The G1(1st generation) has mechanical buttons around the moving mechanical scroll wheel, with each stretching over one quarter of the outer circumference of the wheel.The Gen 1 iPod has a white plastic top plate around the FireWire port, headphone port and 'Hold' switch.ALL 5GB iPod are G1s. (M8513 Mac, M8697 PC). There was never a G2 5GB iPod. G1s weren't only 5GB, however, since there was also a briefly available Mac-only 10GB Gen 1 (M8709).M8513: Original scrollwheel version 5GB (Mac only) M8541: Original scrollwheel version 5GB (Mac only) M8709:

Original 10GB original scrollwheel version (Mac only) M8697: 'New' scrollwheel 5GB PC version2nd Generation iPods (Gen 2, G2, 2G)The G2 (2nd generation) iPod has the same buttons as the Gen 1, but these are located around a non-moving, touch sensitive, solid-state touchwheel. The top plate is primarily stainless steel. The FireWire Port was protected by a built in cover.

The G2s came with the remote and Apple case as standard. There was never a 5GB G2 iPod.The G2 10GB iPod was marginally thinner than the original 5GB iPod and the G1 10GB iPod. (M8737 Mac, M8740 PC). The G2 20GB iPod was marginally thicker than the original 5GB iPod. (M8738 Mac, M8741 PC).M8737: Touchwheel 10GB Mac version M8740: Touchwheel 10GB PC version M8738: Touchwheel 20GB Mac version M8741: Touchwheel 20GB PC version3rd generation iPods (Gen 3, G3, 3G, docking iPod)

The G3 (3rd generation, docking) iPods, also known as docking iPods, introduced a completely new form factor, with a single layer front (white plastic and lucite) and rounded edges front and back. The smaller body houses a smaller battery, of completely new design, with much reduced life.The G3 iPod has four touch sensitive (backlit) buttons in a row above the non moving touchwheel. All G3 models have the new dock connector on the bottom, though the Dock itself is only included with the 15, 20, 30 and 40 GB models, and is an optional extra for the 10GB model, like the case and remote.

The wired remote and headphone plugs have been separated, with separate sockets on the top plate, but remain integrated as one unit.All G3 iPods are Mac compatible 'out of the box'. PC users will have to install and format the iPod for use on Windows with the included software. Even the biggest G3 iPods are thinner than G1s and G2s. (M8976 10GB version, M8946 15GB version, M9244 20GB version, M8948 30GB version and M9245 40GB version)M8976: Touchwheel, 4-button 10GB Mac/PC version M8946: Touchwheel, 4-button 15GB Mac/PC version M8948: Touchwheel, 4-button 30GB Mac/PC version M9244: Touchwheel, 4-button 20GB Mac/PC version M9245: Touchwheel, 4-button 40GB Mac/PC version