A necessory device for your iPod, it is a Universal Dock for iPod . With such a Universal Dock, you can enjoy with a convenient home base for charging and syncing or for connecting iPod to your home audio system. And the S-video port lets you connect iPod to a TV (via optional AV cable) to play photo slideshows and video

Then, you should want to know more about this dock:
Infrared receiver: Control playback from a distance using the optional remote.

Dock connector port: Connect the dock to your computer or an iPod Power Adapter using the cable that came with your iPod.
iPod connector: Place iPod in the Dock to charge the battery, copy songs, and listen to music.

Line out port: Connect speakers using an audio cable with a standard 3.5 millimter stereo miniplug. Or connect an iPod AV cable to view photos or videos (with some iPod models) on a TV or other video device.

To use the dock with your iPod: Attach the cable included with your iPod to your computer or to an iPod power Adapter (sold separately) that’s plugged into an electrical ouotlet, and connect the other end to the Dock.

Chooose the adapter that fits your iPod. Your iPod fits snugly into the correct adapter.