Tamagotchi is a classic virtual pet game that has been around since the late 1990s. In this game, you take care of a virtual pet, raising it from an egg to an adult. You must feed, clean, and play with your pet,
From Wikipedia
Tamagotchi is a brand of handheld digital pets marketed since 1996 by Japanese toymaker Bandai, a division of Bandai Namco Holdings. Most Tamagotchi are housed in a small egg-shaped handheld video game with an interface consisting of three buttons, with the goal of raising the pet as it goes through different life stages.