Subject: Are mature cells in the body able to make copies of themselves?

While studying stem cells, I've come across a number of sources that say stem cells have the unique 
ability to "self-renew"--which is defined as the ability of a cell to make many copies of itself over a long 
period of time.This fact suggests that mature, adult cells, such as a heart cell or a skin cell are unable 
to self-renew. But don't all cells had the ability to undergo mitosis and make copies of themselves? Can 
someone please clarify what is meant by "self-renewal" and how it is different than common cell 
division?

Re: Are mature cells in the body able to make copies of themselves?