cats seem cool, cause I would have a pet but woudln't have to do much. They shit by themselves, they dont need to go for walks.
It's probably a good entry level pet.
Dogs seem more like an animal friend. They can actually do shit. They can play games with you. They can alarm you of danger, and possibly maul some burglar. Some say the smartest dogs have the intelligence level of a 2 year old child. That's pretty cool.
The tradeoff is obviously that you have to do more shit and actually try.
The third pet is obviously human children. They are more sentient, and can be fun for a while, but they grow up to be douchebags.