Chao is a small, colorful creature from the Sonic the Hedgehog video game series. They are often found in the Chao Garden, a special area where players can raise and care for them. Chao can evolve into different forms based on how they are raised, including Hero, Dark, and Neutral types. In the games, players can interact with Chao by feeding them, playing with them, and entering them in races. Chao can also be trained to gain abilities and compete in various challenges. Their cute appearance and unique characteristics make them a beloved feature of the Sonic franchise.