It's a pin-tumbler lock. Except that it seems to have a thin keyway making manouvering picks harder, there is little I can really add.
It's likely a 5, or 6 pin lock.
The part at the back is called the cam - when the plug turns, it turns the cam. The cam operates the latch mechanism it goes into. It is of little importance in terms of picking however so it's of no concern to you.
