Prior to the 70s, most vehicles had the engine in front to drive the rear wheels. The drive shaft was the rotating coupling with universal joints that connected the rear of the transmission (usually under the car around the driver's seat) to the differential assembly at the back of the car. Now with independent suspension and front wheel drive, there are drive shafts (often called axle shafts in this application) between the transmission or differential and the wheels. Also confusing the picture is the popularity of all-wheel and four-wheel drive, where both front and rear wheels are driven. When a four-wheel drive vehicle has a high and low range, there is sometimes another drive shaft between the regular transmission and the high/low two-speed unit. In the most confusing case -- with a four-wheel drive vehicle with independent suspension and high/low range, this means there can be a drive shaft between the regular and high/low gear boxes, one from the rear of the transmission to the rear differential, one from there to the front differential, and two from each differential to the wheels at each corner of the car for a total of seven driveshafts!