Nothing brings out your inner 6-year-old like watching extreme 4x4s roaring to the top of near-vertical cliffs (and bouncing back to the bottom). Vroom vroom! With 4-wheel drive, you think you could go anywhere.

But is 4WD a wise choice for the truck or SUV you use every day? Are all-wheel-drive cars a better choice? What’s the difference between 4WD and AWD, anyway? Here’s the super-speedy explanation.

How 4-Wheel Drive Cars Work

Typically, cars have both a front and a rear differential, which allow the two sets of wheels to rotate at different rates. In an old-school 4WD system, the front and rear drive shafts are linked so the tires spin at exactly the same speed. Imagine driving a Jeep off-road through rocky terrain. One tire might be spinning in the air while another is gripping the ground; because of the 4WD, torque is still applied to every tire.

Driving in 4WD on a flat road, however, can damage the drivetrain. Typically, 4-wheel drive is a system that can be switched on or off, either by the driver or when the car’s computer senses slippery conditions.

How All-Wheel Drive Cars Work

All-wheel drive is a more sophisticated system in which your car’s computer adjusts the amount of power going to each wheel, depending on conditions. If one tire fails to gain traction on an icy road, sensors notice; the computer then sends more power to the wheels that have a better grip. On-demand AWD means your car handles like a front-wheel drive vehicle until slippery conditions are detected and the AWD engages.

Many drivers think that AWD automatically makes a car safer, but the opposite may actually be true. “At the same time AWD doesn’t improve your handling, it does offer an overly optimistic sense of available traction, and it provides the potential to be going so much faster when you need to stop,” Popular Mechanics observes. Nor will AWD help you stop swiftly on slippery roads. That’s all up to your brakes.

AWD vs. 4WD: Which Should You Buy?

The difference between AWD and 4WD has become blurred as car technology has become more advanced. One easy rule of thumb, however, is that AWD is designed to handle bad weather, while 4WD is for conquering tough terrain. When you’re thinking about buying a new truck or SUV, consider these factors:

• Weather: If snow is rare in your state, you’re probably fine with front-wheel drive. All-wheel-drive cars can capably handle normal snow and rain conditions. But if you live somewhere like Buffalo, Flagstaff or Duluth, where hefty snowfalls are the norm, go for 4WD. Four-wheel-drive vehicles can summon the traction necessary to keep you moving through a blizzard.
• Hobbies: If you often venture into the backcountry to go camping or fishing, or you tow a boat or trailer, 4WD is a must. All-wheel-drive cars aren’t made for crossing ditches and streams.
• Cost: Opting for 4WD or AWD can add $2,000 or $3,000 to the cost of an SUV, according to AutoTrader. Car insurance might also be more expensive, especially if you are off-road driving. Not only that, but these systems add weight to a vehicle, reduce the gas mileage and result in more expensive repairs and maintenance.

Just remember that having an AWD or 4WD vehicle isn’t guaranteed to save you from getting stuck in snow, skidding on ice or careening into a ditch. That’s on you and your driving skills!