Who are the pets in WOW?

Profession
Couriers
Summoned Creature
Mount

Info: A pet is a creature called up by a player to help during the battles. Pets are always controlled by the artificial intelligence, but usually a player has the ability to ask a certain number of commands that determine the pet's behavior (for example: attack, defense or guarding). Remember in order to have a pet one has to be a Hunter. A pet will become a good companion in battles only by means of training, taming, feeding, and mood monitoring.