Spend your money on items to keep your pet happy and healthy. Good luck!
The pet's current state has been simplified and represented by just 3 numbers: Hunger, Thirst and Tiredness. In computer science, we call this "Abstraction". Games often take complicated situations (like a plane flying through the air) and simplify them to just a few numbers inside the computer's memory. Another example might be in a game where the player can run around a city. The buildings are simplified models, so you can't go into all of them, open the windows etc. To find out more about how this was created, see the Youtube videos: https://www.youtube.com/watch?v=HUqKb36MqeM https://www.youtube.com/watch?v=-9Cts80dCoU https://www.youtube.com/watch?v=YYdFFB12x5w https://www.youtube.com/watch?v=fhH5J2tBi_U