This USB 2.0 cable connects your iPod, iPhone, or iPad — directly or through a Dock — to your computer's USB port for efficient syncing and charging or to the Apple USB Power Adapter for convenient charging from a wall outlet.
 
A 30-pin to USB cable connects older Apple devices like the iPhone 4S and earlier, iPad (1st-3rd gen), iPod Touch (1st-4th gen), iPod Nano (1st-6th gen), and iPod Classic