A franchise of handheld "digital pet" devices released by Bandai in 1996. The device is egg-shaped and can be held in one hand.
On the screen of the device shows a pixelated "pet" that can be taken care of via the buttons surrounding the device. The pet can get hungry, sleep, get sick, play, misbehave, etc., and the player must respond to these behaviors of the pet (or else the pet dies).
Pets often have lifecycles and may die of old age. Gameplay varies from device to device.