All vehicles are designed to meet certain standards which includes where and how they will be utilized.
Your typical on-road car is often a 2×4, meaning driven by two of the four wheels. And they can be front wheel or rear wheel drive. Often sedans and pickups have rear wheel drive. This being due to the fact that they are preferred in vehicles which are larger and/or load carrying.
AWD -All Wheel Drive
AWD vehicles mostly refer to vehicles which remain on-road most of the time. They are designed for maximum traction on a loose surface. Manufacturers which are involved in dirt rallies tend to have these types of designs. It is in essence more of a ‘soft’ 4×4, such as in sedans, wagons and sports cars. They do not have best ground clearance which is where a true 4×4 thrives.
Some all wheel drive vehicles are made with a bit more ground clearance and electronic traction aids. Though they do not enjoy being on uneven terrain. Yes the vehicle is all wheel drive, but does not mean it is necessarily made for all-terrain driving.
4X4 – Four Wheel Drive
This technology has existed for some time and certainly shows its resilience. 4×4 vehicles have the power from the engine transferred to each of the two axles in such a way that the torque is supplied evenly to all four wheels.
This system has its own flaws. With the torque evenly distributed each wheel will spin at the same time. This is fantastic when you are on uneven terrain looking for traction where you can. But for the everyday on-road drive it can be problematic. When turning the vehicle you want the inner wheels to spin at a slower speed than the outer wheels, something your permanent 4WD does not allow for. And this is just one example.
The modern way around this having a vehicle which allows you to select between 2WD and 4WD via a central differential. Giving you the opportunity to enjoy both worlds.