Hail, good fellow! Welcome to my humble abode. Please, worry not for me-- make thyself comfortable and mind not this garbage that standeth before thee.
JP-1fb is the original design variant. It is an all-around fighter like the raptor. It is moderately fast.
JP-1b is the bomber variant. It is slower than the JP-1fb and is incapable of air to air combat, but is a bit more durable. It is armed with cluster bombs.
JP-1o is the scout and interceptor variant. It is very fast, and has powerful scanning equipment that allows it a greater sight range and the ability to deshroud stealth. It is only very lightly armed, so it is not too useful as a combat aircraft.
JP-1i is the swarm variant. It can only be hosted by the aircraft carrier aerial craft, and cannot be directly controlled. It is faster than the original [i]fb[/i] variant, but is slower than the [i]i[/i] variant. It is similar in purpose to the Protoss Carrier's intereceptors.