Rand is left his home of Farm Town to wander the world, find some excitement, and hopefully make a living. You'll meet him at Coursair, and he'll get more than enough of all three. He's one of the two healers that will join you.
Fighting/Defense -- Rand has high strength and stamina, but his equipment sucks. His defense is about equal to Ryu's for most of the game, while his attack power is about equal to most of the other characters. He's one of your slowest characters, and usually acts last. He has the most HP. He uses knuckles (a la brass knuckles) as his weapon, and can use only a little of the armor.
Special -- Wake. Rand smacks one of your sleeping characters awake. Has a very small chance of reviving a fallen character with one HP. I don't use it.
Magic -- For attack magic, he'll learn Thunder and 8.0. It may be wise to give him one of the bonus spells (Barbose's Missile, to be exact). For healing, he will learn all but CureX and RenewX. He learns healing spells more slowly than Bow.
Shamans -- The Earth Shaman by itself results in a massive defense boost, and a color change. Earth + Water, Fire, or Holy changes him into the Earth Critter -- something that looks like a cross between an armadillo, a rhino, and a rat. Defense gets the highest gain. Special is still wake.
Field -- Rolling. When wandering the world, Rand can curl up in a ball. Steer him with the control pad. To make him stop, crash into something. You'll probably face a random encounter once you stop, but you can't be attacked while in motion. The Earth Critter can't roll.
By level 40 -- He'll have every spell that he can learn, and his defense will be a good bit higher than Ryu. His HP will be a LOT higher than Ryu. He'll be about average in attack power. Give him the Life Bracelet, and he'll be practically unkillable. He isn't the healer that Bow is, but you don't need CureX or RenewX. Cure3 is just fine. He's still slow as molasses, though -- give him some Dinkers, if you decide to use him.