Pokémon has been around since the late '90s and has since produced nine generations; spanning many regions, games, anime series and over 1000 different species. Yet for all the changes and growth that the franchise has shown and embraced over the years, there are certain formulae that have stayed resolute throughout. One of the main ones is the concept of Starter Pokémon. As the name implies, Starter Pokémon are a selection of three Pokémon that Trainers choose between at the start of their journey, and they are always Grass, Water, and Fire types.
Source：https://www.cbr.com/pokmon-starters-generations/
