Front-wheel drive means that only the two front wheels are receiving power from the engine. The rear wheels are not connected to the engine, ever. Front-wheel drive is better in the snow than rear-wheel drive, thanks to the weight of the engine over the driven wheels. However, front-wheel drive is worse than four-wheel drive or all-wheel drive in other poor driving conditions.
One other disadvantage of front-wheel drive is that the engine and transmission are both crammed into the front of the car. So it's often more difficult, and therefore more expensive, to have major repair work done on a front-wheel drive car, compared to a rear-wheel drive model.
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