“The modern method of judicial hanging is called the long drop. This is the method that Iraqi officials used to execute Saddam Hussein. In the long drop, those planning the execution calculate the drop distance required to break the subject’s neck based on his or her weight, height and build. With the knot of the noose placed at the left side of the subject’s neck, under the jaw, the jolt to the neck at the end of the drop is enough to break or dislocate a neck bone called the axis, which in turn should sever the spinal cord” [source]
Sounds ghastly and inhumane but truth is, such hanging when carried out with modern techniques, can be one of the quickest and most painless ways to be executed.