All Blockchain platform has an Architect/designer that lays out detail of operation, in regards of your query about cryptokitties platform you have to address to the designer, if you are planning to become an architect you have to do your research and understanding of programming languages.

I for the life of me don't understand how that game got so popular. I remember early on people were making good money off breeding and selling kitties. Last I had been aware that game had kind of died out because Ethereum transactions got bogged down and expensive and it wasn't really worth the transaction fees to play. Furthermore the whole concept to me was just kinda dumb. A parody game called cryptotitties came out shortly after, same concept just with boobs instead of kitties. I think it got popular because it was the first dApp out there and because crypto was incredibly hot at the time. I've been kind of out of the crypto space for the past 6 or 8 months but I would think the popularity of that game has died off

I just signed up to this website and noticed no one answered your question. CryptoKitties is a great way to explain how "things" are becoming digital. Think of CryptoKitties like your digital baseball card...expect it's a cat card. These cards are digital tokens called an NFT (non-fungible token). All tokens can have different behaviors and attributes. For more information on tokens you can visit the Enterprise Ethereum Alliances Token Toxonomy Initiaive where they define these tokens. Would love to chat more if you have questions.