ignore cat A and B, they are for break only and generally only available to registered dismantlers though they do work their way through to the public. Cat C is beyond economic repair, costs of repairs would exceed value of the car, generally come without V5 and will require a VIC check. Don't worry too much, i've seen saxos with more damage as cat C then some of the break only cars i've bought, on the other hand i've seen them down as cat C for want of a headlight, a joke really! Cat D is pretty much the same as cat C aside from the V5 is usually present. Also don't forget, all this bollocks about i'd never drive a Cat C car is bull, not all have had accidents, i've had cat C's that have been stolen -recovered and needed nothing but insurance have already paid the owner out, i've had plenty of flood damaged ones, need electrics stripping out and repairing, and ones that have been through floods and drawn water into the engine. By that reasoning, guess half the cars on here shouldn't be driven as they've had replacement engines?