What is 4x4 car?

A 4×4 SUV or car, likewise called four-wheel drive (4WD) or 4-by-4, indicates a system in which a car's engine powers all 4 wheels uniformly. Normally speaking, when it involves SUVs and cars, there are only 4 alternatives: rear-wheel drive, front-wheel drive, all-wheel drive (AWD), and four-wheel drive.

The term "4×4" (pronounced four by four) was in use to describe North American military four-wheel-drive vehicles as early as the 1940s, with the first number indicating the number of wheel ends on a vehicle and the second indicating the number of driven wheels.