what year was my macbook released?!

Hi! I recently got a refurbished mac as a present, it was prchased on the apple site. Yet I do not knoq if it is a 2010 or 2011 macbook pro? It is a 17 inch, Intel i7, 8GB of RAM. Could you please tell me some differences between the two macbooks? I really would like to know. Also around the screen, it is an aluminum border. thanks!