Plums are the fruit of the wide ranging genus Prunus, which includes old world plums, new world plums, and apricots. Plums are grown around the world, and are used for various culinary uses, including fermentation into wine, distillation into brandy, pickling (in Japan called umeboshi), drying (dried plums are called prunes, which are being renamed dried plums to avoid the connotation that prunes are for old people needing a laxative) and salt-curing.
Most of the common plums in the grocery store are Prunus domesticus. Some other less common varieties are the Damson plum (P. insititia), and the sloe, or blackthorn plum (P. spinosa), which is used to make sloe gin. In France, the Mirabelle (P. x domestica ssp. syriaca) is grown in the Alsace region of France, and it used to produce the fruit brandy of the same name.
Plums come in a range of colors, from green to yellow to red, purple and bluish-black.
Plums are grown on trees, like all stone fruit, and sometimes have a waxy coating or bloom on the skin. Like all stone fruit, the pit contains cyanide-forming compounds, so care should be taken macerating pits in alcohol.