Virtual pet

In these worlds, a user can play games to earn virtual money which is usually spent on items and food for pets.

There are many video games that focus on the care, raising, breeding or exhibition of simulated animals.

Pet-raising simulations often lack a victory condition or challenge, and can be classified as software toys.

"This quality of rich intelligence distinguishes artificial pets from other kinds of A-life, in which individuals have simple rules but the population as a whole develops emergent properties".

PF.Magic released the first widely popular virtual pets in 1995 with Dogz,[5] followed by Catz in the spring of 1996, eventually becoming a franchise known as Petz.

[citation needed] A Mad cover on regular issue #362, October 1997 shows a gun being pointed at a virtual pet with Alfred E. Neuman's face and the line "If you don't buy this magazine, we'll kill this virtual pet!"

With advanced video gaming technology, most modern digital pets do not show a message box nor icon to display the pet's internal variable, health state or emotion like earlier generations (such as Tamagotchi).

Instead, users can only understand the pet by interpreting their actions, body language, facial expressions, etc.

To give a sense of reality to users, most digital pets have certain level of autonomy and unpredictability.

Long-term interactivity includes action that affects the pet's growth, behavior or life span.

Long-term interactivity is quite important for a sense of reality as the user would think that he has some lasting influence on the pet.