Discussions center around safety and comfort. Rental fleets are generally outfitted with micro-adjustable footpegs because they are quicker to adjust, can be adjusted in smaller increments and give better access to installing bow floatbags. Some believe footpegs are safer in that they tend to break before your ankles in case of a piton. Some of the smaller playboats on the market have room for neither, instead relying on the user to insert small pieces of foam. Hard chines help the boat carve when leaned.
Rails are any edge of the boat at or above the waterline.
Planing hulls are flat-bottoms designed to help the craft surf, spin and maneuver. Manufacturers have a good idea of what size paddler will most enjoy a certain model. Whitewater kayak materials are broken down into composites and plastics. Rotomolding is often utilized for optimum strength. Crosslinked is known to have good shape-retention and warp resistance, but is harder to repair.