SOME TYPES OF COMMON, POPULAR POTATOES:

RUSSET
Perhaps the best-known potato in North America. Thick skin, large, reliable, hardy, flesh becomes very soft after cooking and is good for mashing, frying, baking. High in starch. Also known as the Idaho potato. You could call it 'old faithful', you see it everywhere, performs well for home cooking and processed foods. There are many kinds of Russet but usually when you see one, you know it. Below: Russets.

WHITES: LONG WHITE and ROUND WHITE
These are thin-skinned potatoes, with medium starch content, very versatile and agreeable to almost any use you can think of for a potato. They hold together well and are perhaps the most common potato in making potato chips. Below: Long Whites and Round Whites.

NEW POTATOES
This is actually not a variety of potato, it refers to young potatoes of any kind. Think of them as adolescent potatoes. They tend to be very soft, moist, small, and thin skinned. Prized highly for their young, fresh taste and firm, smooth texture. Below: white and red new potatoes, and some cooked new potatoes.

ROUND RED
Red potatoes are attractive, small to medium sized potatoes, and are versatile like the whites. They are firm, moist, and have a nice smooth texture, so are ideal for salads, baking and roasting.

YELLOW
Yellow potatoes come in many varieties, and are usually a very soft potato so work well in mashed potato recipes, but don't hold together firmly enough for things like fries and salads. They tend to seem a little buttery and lean towards a slightly sweet taste. Below: Yellow Finn, and Yukon Golds.

PURPLE AND BLUE
Rarely used, these still have nice qualities, interesting looks, and are used for potato chips and recipes where an exotic look and slightly nutty flavor is wanted. Below: Purple potatoes, and purple potato chips.