The grape is the fruit of the (grape) vine, and has long been prized both as a refreshing, self-wrapped, succulent treat (which can also be reduced to juice or to jelly), and also, once allowed to rot and ferment, as the basis for wine.
The raisin is the dried, unfermented form of the grape (its name coming from the French word for 'grape'). the currant is the dried Zante grape (the name being drawn from raisin de Corinthe (Corinhtean grape). The sultana, in period, was a dried Turkish grape.
The main European species is vina vinifera.
The coloration of wine has little to do with the colour of the grape (which can vary from golden to near-black, through reds and purples), and much to do with whether or not the skins are left in the fermentation process (thereby allowing their colour to leech out), are are removed, which produces a "white" wine.