What is the difference between all-wheel drive and four-wheel drive?

All-wheel drive (AWD) and four-wheel drive (4WD) both send power to all four wheels, but they work differently and suit different purposes. AWD systems operate automatically and continuously, distributing power between front and rear wheels as needed without driver input. They are common in cars and crossovers and are designed for everyday use on wet or slippery roads. Four-wheel drive is typically a more rugged system found on trucks and SUVs. It usually requires the driver to manually engage it and often includes low-range gearing for serious off-road situations like rock crawling or deep mud. Running 4WD on dry pavement can cause drivetrain stress, whereas AWD is safe to use at all times on any surface.