Always wash stone fruit before eating. Stone fruit can be used whole or cut in half and the stone removed. The inner kernel of apricot stones can be simmered with the fruit when poaching to add an almond flavour.
In some dishes, the skin of stone fruit is also removed, such as with poached peaches or nectarines. However, since the skin adds a beautiful colour to the poaching liquid, it is usually not removed until after the fruit is cooked.
Damsons and some varieties of cooking plums have a high pectin content so make excellent jam; apricots, greengages and other plum varieties have a medium pectin content, so need lemon juice to help them set; peaches, nectarines and cherries have a low pectin content and need extra pectin or other pectin-rich fruit to set.
All stone fruit make good pickles and are delicious preserved in alcohol.