The good fats are monounsaturated (the best kind) and polyunsaturated (to a degree). Also moderate amounts of saturated fat can't hurt you. The only really bad fat is trans-fat, which is included in processed goods, margarines, and the like. Avoid it completely.

As for cravings, I'm with you! What helps me is to have a salad with LOTS of olive oil. The rich, healthful fat really cuts down on the sugar cravings--trust me, it works, and it's completely legal on induction.

Good luck!