If you spend your time on a Role-Playing server and enjoying RPing, your choice of profession will have some impact on your character outside of just an easy supply of potions, scrolls, or bullets. Think about your character's back story, and which profession fits into whom you feel he or she really is.

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Some races lend themselves to certain professions, and may even have a racial bonus for that job. For instance, Humans, Dwarves, and Orcs get a bonus to certain weapon skills, so you could make a case for a toon of those races taking
Blacksmithing and specializing as a Weaponsmith. Likewise, it makes sense that an ancestor of failed Gnomeregan should have an affinity for Engineering. The cultures of both Tauren and Night Elves lend themselves to Herbalism, although only the Horde race receives a bonus to the skill, and one can easily imagine the shadowy Undead experimenting deep into the night with
Alchemy.
Of course, class figures into the decision heavily, as well. Although Rogues no longer have to brew their own poisons, they do still enjoy mixing up a batch of Free Action or Swiftness Potions. Likewise, Hunters and Druids understand the importance of beasts in our world, and will take both meat and skins from their kills in order not to cause waste.