Rear-wheel drive means that your car’s engine is powering only the two rear wheels.
The disadvantage of rear-wheel drive is that, unless the car is very heavy, its traction is lousy in the snow and not so great in the rain, either. Even with traction enhancements such as limited slip differential and electronic traction control, it's impossible to match the traction a front-wheel-drive car gets thanks to the hundreds of pounds of engine and transmission weight that are sitting right over the front wheels.
Rear-wheel drive cars have a small advantage over front-wheel drive cars when the weather isn’t foul. In a rear-wheel-drive car, a big part of the transmission, called the differential, is in the back instead of the front. That helps bring the car's overall weight distribution closer to 50-50, which makes for slightly better handling.
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