This is a list of every Tamagotchi virtual pet ever released, in chronological order.
The original Tamagotchi was a virtual pet created in Japan by Akihiro Yokoi of WiZ Co. Ltd., and Aki Maita of Bandai Co. Ltd. It was released in Japan in 1996, then in America and Europe in 1997. It had one baby character, one toddler character, two teen characters, and seven adult characters, for a total of 11 characters. One of the adult characters was a "secret" character, which could eventually appear from one of the other adult characters if given a certain level of care. The screen of the device featured a 16 x 32 squared dot matrix where the character was displayed.
The Tamagotchi Generation Two is very similar to Generation One in terms of programming. The two "generations" have different characters and a different game in each, and a number of other minor differences, such as small differences in the Meal and Snack options,the background of the Tamagotchi and in the animation that is shown at the end of a Tamagotchi's life.Also, the packaging has several differences.
The Tenshitchi no Tamagotchi was released in Japan in August 1997 with three different designs, and a later English version, the Tamagotchi Angel, was released in America and Europe with four designs.
The Mesutchi and Osutchi were released in December of 1997 in Japan only. They feature interlocking mating using the same interlocking technology that Digimon used to connect, in which the tops of each Tamagotchi would lock together so that they could communicate with each other. When a Mesutchi and Osutchi connect in the adult stage, their mating may result to a child.
Both Mesutchi and Osutchi feature 31 characters each. Four different generations, or TMPs, of Tamagotchi are available, but only the first one grows in a way that is affected by caretaking skills; the other three are linear. If the caretaker is not responsible in their care for their Mesutchi or Osutchi, the Tamagotchi will become an adult character uninterested in love. If the caretaker feeds the Tamagotchi too much food and it becomes overweight, it will turn into a "Debutchi" which takes up the whole screen. In this state, the user can not do anything with the Mesutchi or Osutchi except play the game and check health status. The caretaker then has to lower the weight of the Tamagotchi by playing the game before normal functions may resume.
The Mori de Hakken! Tamagotch, commonly referred to as the Mori no Tamagotch, was released in February 1998 with four different designs. It was scheduled for release in America as "Tamagotchi Garden" but was not released. This Tamagotchi introduced the "predator" function also used in the later Umi de Hakken! Tamagotch (Tamagotchi Ocean). Occasionally a predator attacks, and the care taker has to use the sound-sensitive functions introduced in the Angelgotchi by shouting or tapping at the screen to frighten away the attacker. If the attack is a success, the Tamagotchi may become seriously injured or even die.