Diablo III Classes Geek
Diablo III will have five classes: the Barbarian, Witch Doctor, Wizard. Monk, and Demon Hunter.
the Barbarian
The Barbarian returns from Diablo 2 as the straightforward brute-force fighter, with some new abilities as well. The Barbarian's mechanics seem very similar to those in the last game, with most moves being very close range, with exceptions such as the Leap ability.
Witch Doctor
The Witch Doctor will be a new class. They can summon undead monsters, but without the need of dead bodies like the Necromancer. They appear to be a mixture of the Necromancer, the Druid and an alchemist, with some skills also reminiscent of the Warlock from World of Warcraft, such as Terrify and Mass Confusion. While these are old Necromancer skills, they are much more potent now.
Wizard
The Wizard is the run-of-the-mill magic user in Diablo III combining the brilliance of the Sorceress and the cunning and stealth of the Assassin. Only the female Wizard was playable in Blizzcon, the male Wizard's gameplay was revealed a few days later. Jay Wilson had stated that fans will "hate" one of the new classes for the game, courtesy of it resembling a former one. But, seeing the attitude of the new Wizard compared to its brooding predecessors and the powerful skills it wields, fans have taken a certain liking for the Wizard.
Monk
The Monk is another melee based class. It appears to rely entirely, or at least mostly on its fists and fist based weapons similar to the weapon choice of the Assassin in the previous game. Some attacks will have a limited range, so not all combat occurs at very close range. He also possess holy-light abilities with allow for healing.
Demon Hunter
The Demon Hunter is a new class being introduced in Diablo 3. With what gameplay Blizzard have shown of it, the Demon Hunter looks to be a combination of the Assassin; with its ability to throw grenades, and the Amazon in its usage of crossbows. However the class looks as if it is going to dual-wield a crossbow which is a completely original concept in reference to prior games.
Diablo III Classes Gallery
Diablo III Classes Video
Source: http://diablo.wikia.com/wiki/Diablo_III