First off lets talk about Melee jobs. These are jobs that wield swords and the like as they enter battle.

Warrior
A Warrior is a swordsman that can wield loads of swords, and is the basic of basics in melee jobs. They have good offense and defence, but thier magic can't match.

Berserker
A berserker is a primitive looking melee job that has a constant beserk effect as it would seem. They have lots of energy in those nasty little claws, and can avoid damage to an excellence. In FFX-2, thier's a lot more they can do indeed, like hitting back when they are attacked in anyway.

Knight

A knight is a highly defensive swordsman. And they certainly do need that defence in dire times! If the rest of your team aren't doing so hot, a Knight will step in and take the damage, and it only does half damage.

Viking

A Viking, the ancient armies of ancient Norway, (I think,) are very strong and good in health and defense. They wield axes and hammers rather then pesky swords. The special effect Vikings posses, is they can provoke an enemy into not attacking the Viking's friends, but attack him/her instead. Watch out, this can put your viking in a bad situation. Also, these guys take FOREVER to level up.

Monk
A monk is a hand-to-hand combat specialist who's punch packs, well a punch. Extremely helpful, and can activate a counter ability so they can beat the enemy up, after hurting the Monk.

Black Belt
A black belt, is a much more powerful monk in a sense. They can easily KO an enemy, and can use a focus ability. This makes thier power increase, so its worse for the enemy. There's a sneaky catch to this. Too much focus, can be painful. When it hurts the Black belt, I advise you beat the poop out of your enemies.

Samurai
A Samurai is a Japanese themed melee swordsman that can easily kill enemies with a fireworks attack. If you have enough money, you can throw some loose change at the enemy.

Thief

A Thief is not a nice thing for the enemy. They penny pinch, item pinch anything pinch everything from the enemy. They are also really quick and can flee, which lets enemies follow up on thier actions. Everything has a price though, like a Thief's low defence.

Ninja
Another Japanese themed job, Ninjas are quick on thier feet. If you need to, you can throw unequipped equipment and items at the enemy. Shuriken do THE highest amount of damage. They have little defence though.

Dragoon
Dragoon. Wierd name, VERY fun job! The user can jump, extremely high for one turn, and on the next, come crashing down on the enemies and remember, this is potentially fatal on your mean enemies!

Trainer

A trainer is someone who owns an animal and uses them to attack the opponents. In other games, a trainer captures a beast and uses THEM for pets.

Hunter
Also known as the Gunner, Archer, Ranger, the Hunter specialises in long range attacks. These guys can AIM thier attacks and fire! Also, sometimes they can send volleys of ammo at the enemy.

Those are ALL The Melee jobs.