The Pokédex is the device in Pokémon games that records information about captured species.
The name combines “Pokémon” with “index.” In the original games, Professor Oak gives the player a Pokédex and asks them to document the Pokémon found in the Kanto region. A species is generally registered when the player encounters it, while fuller information is recorded after catching it.
Later games expanded the idea with regional Pokédexes, National Pokédex numbers, habitats, forms, cries, heights, weights, and evolution data. The in-game device is usually presented as an electronic encyclopedia rather than a simple checklist.
Other Pokémon devices have different roles. The Pokégear provides communication and map functions, while the PokéNav appears in Hoenn games. The Pokédex remains one of the franchise’s most recognizable pieces of equipment.