There are many foods which are eaten when dried, and sometimes we give this dried version of the food a completely separate name. An example of this would be a prune, which is actually a dried plum.
But what about raisins? Are raisins actually dried grapes?
Yes, they are!
Raisins are made when grapes are allowed to sun dry. This loss of moisture is the reason that raisins are typically smaller than grapes. Also, during the drying process much of the natural sugars in the grape will concentrate and crystallize, which is what gives raisins their sweeter taste.
Lighter colored dry grapes are sometimes called sultana raisins, while dried black corinth grapes are known as currants.