Though the Robot was not invented by the brothers, it was made accessible to the masses the first time Michael displayed the dance on the "Merv Griffin Show" in 1974 while performing their hit single, "Dancing Machine."
The Robot consists of a series of jerky motions in concert with the beat of the music, usually funk with a hard-hitting bass line. The feet shuffle in such a manner that allows the body to appear to be gliding across the floor in the manner of a robot. The arms move in what can best be described as stop-motion; they move back and forth as if mechanical, giving the illusion of robotic motion. Those who are able to hear the music and follow its bass line are fully capable of hitting each beat in a syncopated rhythm.
Though not as known in the modern-day mainstream, the almost military precision of the brothers defined their style to a generation of fans and performers alike. Most notably is the step-kick shuffle seen in most of their performances. The dancer begins with what appears to be a small jog/shuffle. Beginning with the right foot lifted up as in a jog, the dancer makes a short quick kick with the left foot. Then the move alternates. The left foot goes up and the right foot makes a short quick kick. This step-kick continues four or five times.
Another move, made popular in the group's performance of "I Want You Back," is one in which the dancer twists and juts his or her hands out. Beginning at the bottom, the legs twist from side to side. At the top, the hands alternate between each other in a rolling motion. On the third beat, the dancer moves the right leg back and the right hand juts down, on the fourth, the left side does the same thing.
All these dance moves, of course, are more interesting to watch than they are to explain. You can't read how to do it. You must try it. Watch, absorb and execute. To understand these moves, you must practice, practice, practice.