Grapes for commerce are divided in to 4 major and one minor groups according to their use.  These groups are table grapes, raisin grapes, wine grapes, juice grapes, and the minor group of canning grapes. There are more than 8,000 named varieties but only a limited number are used to produce quality wine and only about 3 are used to produce commercial raisins. Fewer than a dozen varieties are grown for the table grape market.  Most of the juice produced in America is from the Concord variety which is also used extensively for jams and jellies.   Among the many varieties are Thompson Seedless, Catawba, Concord, Flame Tokay, Muscadine, white Malagas, Niagras, Delaware, Worden and Barbarossa.