As a hunter, you can tame a pet that will help you killing NPC’s or other players. Many beasts are tameable, like spiders, cats, wolves, birds, and if you are specced in the beastmastery talent tree, you can even tame some cool looking spectral pets.
One of my friends send me this question: “I have had a cat for ages. Do different cats/pets have different stats that could improve dps? If so whats the best pet to have?“
Yes, indeed. Different pets have different stats, and the best pet to have? That depends entirely of your purpose for that pet.
In short, if you’re doing PvP, many recommend spiders as the best pet, since it has venom, and it can stop players with their webs.
For dps in PvE, I prefer a cat. A cat has the highest dps of the pets, but some say that a wolf is better because of the buff, it gives. I’ve never found out which buff, they’re talking about, but in my experience, a cat works better for me. I’ve tried both cat and wolf from low level, and I prefer a cat.
Some pets are great as tanks, as for example bears.
All of the hunter’s pets are divided in classes.
You have the cunning pets, which are birds, spiders and snakes. These are also called balanced pets.
The ferocity class contains wolves, cats, raptors, and one bird. These pets are great for dps.
If you want a tank pet, choose one from the tenacity class. There you’ll find scorpids, gorillas, turtles, bears, and warp stalkers among others.
Each and every pet group (like cats) have their speciality. You get a great overview over hunter’s pets at WoWWiki and from this guide, which places the wolves in a more appropriate category, I think: WoW Hunter Pet Guide.