Auto Shuffle Train
Auto Shuffle Train/Signal Speed Control, is where a system can tell a train what to do automatically, without any input from the user. For instance if a signal is red, the system might tell any loco approaching that signal to slow down and stop, then when the signal turns green the system will tell that loco to gradually accelerate until it reaches it's original speed setting. Or it could tell that a train that has reached the end of a branch line to stop, wait a few minutes then accelerate back in the opposite direction.
An auto stopping module is basically an integrated command station and booster which is connected to its own block. It basically generates a generic DCC packet with the "Stop" command, so any decoder in that block will be affected regardless of the decoder's address.
Also See: Asymmetric DCC for a similar implementation.