Druid
Druids are versatile hybrids with various shapeshift forms in which they can tank like a warrior (Bear Form), stealth and fight in melee like a rogue (Cat Form), heal like a priest (normal or Tree Form), and cast spells like a mage (normal form or Moonkin Form).
Hunter
Hunters are the only class that can effectively use ranged weapons (e.g. bows or guns) as a primary source of damage. Very adept at kiting, they have plenty of tools to allow them to avoid melee combat, where they are fairly weak.
Paladin
A hybrid class focused on defensive melee skills and healing abilities, paladins have very strong group support and buff abilities. They may wear heavy plate armor and carry shields like a warrior, but are also efficient healers, which combine to produce their renowned durability in combat.
Mage
Mages are ranged magic damage dealers with very powerful direct and area effect damage spells, but weak armor and health. They also feature a variety of utility spells, including crowd control, teleportation and group portals to capital cities, and conjuration of food and water.
Rogue
Rogues excel at dealing melee damage and incapacitating their foes, particularly low health and low armor targets such as casters. Stealth gives them a tactical advantage and allows them to start a fight on their own terms. Other important abilities include lockpicking and the creation and handling of poisons.
Priest
Priests are the quintessential healer, and easily the most versatile class in that role, though they may also specialize to become powerful offensive casters. Priests have a wide variety of healing utility spells, along with a few tricks, helpful and otherwise, such as Power Word: Fortitude, Mind Control and the extremely useful Dispel Magic and Cure Disease.
Warrior
Warriors are close-combat fighters and usually fill the role of primary tank or offtank, as they are able to both withstand and inflict fierce physical punishment and have the most versatile means of generating threat and keeping aggro off other characters.
Shaman
Shamans are one of the most versatile classes in the game as they can switch seamlessly from offensive caster to healer to melee DPS as needed, though at later levels they often specialize in one of these roles. Shamans can make good support characters, with the ability to step in and fill any role that may be lacking at the moment.
Warlock
Warlocks enslave demons and call upon dark magic and curses to dominate and destroy their foes. Like hunters, warlocks employ combat pets, but these are summoned demons rather than tamed beasts.
Alchemi
The alchemist mixes herbs and reagents in order to generate elixirs, potions, oils, flasks, and cauldrons with a variety of effects. A player can create healing, invisibility, elemental resistance, and mana potions; oils to coat weapons; and much more.
Enchanting
Enchanting is a primary profession in which characters may enchant and craft a variety of items with useful effects. Most trade skills have a flat learning curve.
Blacksmithing
Blacksmiths take bars of metal from miners and work them into finely crafted arms and armor. There are many unique weapons and other armaments that cannot be found on any of the vendors or monsters in the game; these can only be created by blacksmiths.
Leatherworking
The Leatherworking profession allows players to utilize the Leather gathered through the Skinning profession to create a variety of items, including cloaks, leather and mail armors, armor kits, quivers, and ammo pouches.
Engineering
Engineering is a primary profession in which characters may craft a variety of items with useful (and sometimes unpredictable) effects. Consumable devices can provide supplemental damage from explosives, aggro diversion and situational advantages (Discombobulator Ray and Field Repair Bot 74A).
Jewelcrafting
Jewelcrafting is a profession which was introduced in the Burning Crusade expansion. Players are able to make rings, trinkets, necklaces and more, as well as gems for socketed weapons and armor. Special for any Jewelcrafters are Figurines which are Bind on Pickup.



