Pad compound is the choice most people actually need to make. Ceramic runs quieter and cleaner for daily driving. Semi-metallic bites harder and handles heat better under load. Organic sits between the two and wears faster.
Rotors list diameter and thickness, and where a rotor is coated, the coating is noted. Coated rotors resist flash rust on the hat and edges, which matters in wet climates. Calipers note whether they are loaded with pads and whether the bracket is included.
