A hybrid system is a storm which has some tropical characteristics and has other characteristics that are not tropical in nature. Its difficult to tell which is which by the way they look on say, a satellite page we laypersons might look at, but the meterologists can look at the way the storm behaves, what the pressures are and how the storm responds to the atmosphere around it and can tell that this system is or is not a hybrid. The hybrid storms usually appear late in the storm season around late October/November and they do some weird things sometimes like go the opposite direction that storms are expected to go according to the climate.