Ever gaining in popularity, over 45 percent of new vehicles sold in the U.S. have either all-wheel drive (AWD) or four-wheel drive (4WD), according to an Edmunds analysis. There are many reasons why car buyers are trending towards the drivetrains that allow for more traction, control and power. These two terms can be confusing and even used interchangeably, so it is important to distinguish the pros and cons of the different systems to make the most informed decision as to what would be best for your specific needs.