Pichu is an Electric-type baby Pokémon introduced in Generation II.
It evolves into Pikachu when leveled up with high friendship, which evolves into Raichu when exposed to a Thunder Stone.
Pichu is a social Pokémon known for its playful and mischievous demeanor. It is usually found in groups and often touch tails with other Pichu as a show of courage, creating a shower of sparks that can make them cry. It is inept at storing electricity and may discharge if amused, startled, or subjected to shock. However, it cannot discharge without being shocked itself. Charging up is more easily done on days of dryness or with thunderclouds. The crackling of static electricity generated by Pichu is audible. It can zap an adult human but will surprise itself if it does. Pichu primarily lives in the forest, though it has also been depicted to thrive in urban areas.
Pichu has an alternate form called Spiky-eared Pichu that appeared in Pokémon HeartGold and SoulSilver, as well as the anime and the manga. This form is female-only and has three spikes on the tip of its ear, but otherwise looks the same as any other Pichu.