There are thousands of varieties of grapes grown worldwide. Most wines, however, come from the classic European grapes
in the Vitis vinifera family. These wine varietals are
a subspecies of grape from vinifera with names like Pinot Noir and Chardonnay.

Some white wines are made from red grapes. Pinot Grigio grapes have red skins, but contain a grey-white juice on the inside. In fact, most red grapes give off white juice. The juice is left in contact with the skins after it's been crushed to let it pick up color and flavor.

White Zinfandel is actually pink, and half way between red wine and white. To make the sweet blush wine, winemakers allow the light colored Zinfandel juice to remain in contact for the first hour or two after extraction, then it's allowed to run off. This is how White Zinfandel gets it's pink hue.

Complement:
When choosing wines that "complement" the meal, the
flavor in the food tends to match the same flavor in the wine,
often highlighting other flavor complexities. For example, a Cabernet Sauvignon with hints of mint complement a lamb with mint sauce.

Contrast:
Another way to choose good pairings is to "contrast" flavors. For example, if you were to serve shrimp sauteed with olive oil and garlic, a good wine to pair is a crisp Chardonnay with lots of citrus. The citrus and acid in the Chardonnay contrast with the shrimp in much the same way as a twist of lemon would. It’s like adding and extra ingredient to the dish. Contrasting wines with food uses a distinct flavor in the wine like an added seasoning.