Chocobos vary in many ways -- they're not just a bunch of useless birds. We've compiled a Chocobo guide showing the strengths and weaknesses of each kind of Chocobo.
The Yellow Chocobo
The Yellow Chocobo is used for defensive purposes only. It has unlimited Chocobo cures. This guy comes in handy when you're all out of healing spells and items. This one is very useful when you're first starting off.
The Black Chocobo
The Black Chocobo has the most hit-points and striking power out of all the Chocobos -- need we say more.
The Red Chocobo
The Red Chocobo is the best one out of them all. There are two ways of getting it: having it born into your party or inviting (Mediators - Invite skill) it into your party during battle. And once these suckers start gaining spells, they become a pretty lethal force.