Baitcaster or spinning reel? Research as much as you like and you’ll find that many anglers have used both but prefer one type over the other. Mechanically speaking, reels, both baitcasting and spinning, have their advantages and disadvantages.
Spinning reels are designed with a stationary spool and a rotating line-winding mechanism which is great for low-torque situations and therefore perfect for light angling—typically fish less than fifteen pounds.
Baitcasters have line running directly off a fixed rotating spool—much more torque and therefore excellent for fishing in deep cover situations and when using bigger baits for bigger fish.
To truly cover as many fishing situations as possible though, an angler definitely benefits from knowing how to use both.