A Raisin is a sun-dried or artificially dried grape, used in cooking and baking. Raisins are extremely sweet due to their high sugar content, and if they are stored for a long period the sugar crystallises inside the fruit. This makes the fruit gritty, but does not affect the usability. To decrystalise raisins, they can be soaked in liquid (alcohol, fruit juice or boiling water) for a short period, dissolving the sugar.
In the USA, the term 'raisin' refers to any form of dried grape, but some varieties are known by other names such as zante currant, or golden raisin. In Australia and other countries specific varieties are given separate names - see sultana, currant.
Raisin is also a dark purple color (the color of a raisin)
Raisin was also the musical version (music by Judd Woldin; lyrics by Robert Brittan; book by Charlotte Zaltzberg and Robert Nemiroff) of the play A Raisin in the Sun, written by Lorraine Hansberry.