There are 18 Pokémon types as of Generation 9. Types are categories that describe a Pokémon’s elemental or thematic nature and determine how its moves interact in battle.
The 18 types are Normal, Fire, Water, Electric, Grass, Ice, Fighting, Poison, Ground, Flying, Psychic, Bug, Rock, Ghost, Dragon, Dark, Steel and Fairy. A Pokémon may have one type or two, while individual moves also have types that affect damage and strategic matchups.
The type system began with 15 types in the first-generation games Pokémon Red, Green, Blue and Yellow. Dark and Steel were added in Generation 2, and Fairy was introduced in Generation 6. No new standard type was added in Generation 9, so the total remained 18.
A common mistake is counting dual-type combinations rather than the types themselves. There are many possible combinations, but only 18 basic type categories. Terastalization in Pokémon Scarlet and Violet can also temporarily change a Pokémon’s battle type, without increasing the number of standard types.