Baitcaster and Spinning
You would think there's only one way but gripping is different. I mainly hold at the trigger, sometimes I'll double finger the trigger. I don't palm a baitcaster but then again I've seen different palm techniques used.
Spinning, there's different ways where you can grip the reel, and even not at all, when I cast ill grip with the pinky/ring then switch over to the ring/middle for better hold.