There are more than 200 varieties of peaches sold commercially from California and 40 commercial varieties from Georgia. The two most common types of peaches are clingstone and freestone.
Clingstone peaches have a firm flesh that clings to the pit. It can be sliced off with a knife.
Freestone peaches are available as the summer progresses and have a juicy, soft flesh that’s easily separated from the pit.
Taken From: http://www.fruitandveggieguru.com/Peaches.html?pccid=33&tabid=70&kw=Peaches