There are more than 200 varieties of potatoes sold throughout the United States. Each of these varieties fit into one of seven potato type categories: russet, red, white, yellow, blue/purple, fingerling and petite. These types can be generally categorized into three different groups(Starchy, Waxy, and All Purpose) based on their cooked texture and functionality.
Starchy:
Also known as “mealy,” starchy potatoes, which include Russets, Idahos and many yams and sweet potato varieties, are, as the descriptor says, high in starch. They are also low in moisture, fluffy and absorbent, making them ideal for baking, frying, boiling, and mashing. Because the flesh flakes and separates easily after cooking, they do not hold their shape compared to waxy potatoes.
Waxy:
Waxy potatoes are low in starch, high in sugar and moisture, and tend to hold their shape, even after cooking. They have thinner skin, a smoother texture and are generally smaller and rounder. Common varieties include French fingerling or Red Bliss. They hold their shape well after cooking, they’re ideal for boiling, roasting and incorporating in dishes like gratins or potato salad, where you’ll want the potato to stay intact.
All-Purpose:
All-purpose potatoes, like Yukon Golds, fall somewhere in the middle. They are less starchy than your typical high-starch potato and hold their shape better than them, too. But they are decently absorbent and fluffy, making them suitable for any type of potato dish, especially in a pinch. These can be used for mashed potatoes, as well.