The trap bar (or hex/hexagon bar) is a barbell with a middle portion that is shaped like a hexagon. With a distance of about 1.5 times shoulder width, the trap bar has handles in the middle, which make lifting more comfortable. As a rule, a bar weighs about 45 lbs.
The trap bar was developed in the 1980s by Al Gerard, an American powerlifter, with the goal of relieving back strain during weightlifting.
The best known exercise for training with the trap bar is the deadlift. Here you have an enormous advantage compared to the deadlift with a normal barbell. The trap bar allows for a more natural movement; because of the raised grip position, you don't have to shift your body weight as far back as when lifting a barbell.
When deadlifting with the trap bar, you stand in the hexagonal area of the bar and do not touch the bar with your shins. Thus, you lift the weight more from the center of your body and have a lighter load on your spine.
Learning the technique with the trap bar is much easier than it is with a normal bar. In addition, the training is much gentler on your lower back and spinal discs.
Other trap bar exercises include different variations of the deadlift and the shrug.