There are 18 types of Pokémon. Each Pokémon has one or two types, which determine their strengths, weaknesses, and abilities. These types include Normal, Fire, Water, Grass, Electric, Ice, Fighting, Poison, Ground, Flying, Psychic, Bug, Rock, Ghost, Dark, Dragon, Steel, and Fairy. Each type has its own set of moves and interactions with other types, creating a complex battle system in the Pokémon games.