Which animal makes a better pet?

I have never had pet,so I can't write from my experience, but I think that dogs are better pet. Because I have ever heard that dogs are very loyalty, and if we live with a dog, we can learn many things from a dog. When we are young, dog is a playmate, and we are growth together. So, I think that especialy if we are an only child, we should have a dog. If we have a dog, we have to discipline strictly. Maybe it is so hard, but it have very important means.