Potatoes can be divided into two main categories -- starchy and waxy. Starchy potatoes such as russets are fluffy and floury when cooked. Waxy varieties, such as new potatoes and fingerlings, are low in starch, have a creamy texture, and hold their shape well when cooked.
Yukon Golds are considered a waxy potato but have a slightly higher starch content, so they're especially versatile.
Buying and Storing
Look for potatoes that are firm and free of cracks and bruises. Avoid potatoes that have sprouted "eyes" or have green-tinged skin -- both signs of improper storage. Store potatoes in a cool, dark place (not the refrigerator). Waxy potatoes are best used within a week, while starchy varieties keep for several months.
Pair potatoes with the cooking methods that suit them best. Fingerling and new potatoes are great steamed, boiled, sauteed, or roasted. Yukon Golds can be prepared like other waxy potatoes and are especially delicious when mashed. Russet potatoes can be sauteed, baked, cooked in gratins, or fried.