The pedal steel guitar is only distantly related to the more traditional Hawaiian steel, the big difference being the pedals. Like its Hawaiian cousin, the pedal steel is played (in part) by sliding a steel bar up and down the strings, but that's where all similarity ends. Because of the inflexible nature of the steel bar, it is impossible to play different strings in different places simultaneously on a non-pedal instrument. If the guitar is tuned to a major chord, you are stuck with that chord. There is no way to make it minor. Players have gotten around this by using several extended chord tunings which contains both major and minor triads, but clearly there are still many harmonic limitations.

By contrast the pedal steel guitar allows for an unlimited number of different chords and inversion. This is accomplished by a system of pedals and knee levers that mechanically alter the tuning while you play. This means that the notes don't consistently appear in the same place. Middle C for instance appears in 4 different positions on the same string. The pedals can work in the same direction as the bar movement or in the opposing direction, thus it is not only possible but quite common to raise the bar a whole step and have the pitch raise by 2 steps, or a step and a half, or stay the same, or even lower.Another way of putting it is that there is no fixed relationship between the left hand position and the resultant pitch, but rather a continually shifting relationship.

Clearly this is a very complicated instrument to learn. It does not conform to the most basic rules of how stringed instruments work, but within its own convoluted logic it does make sense. It has its own logic that doesn't relate to any other instrument. Physically, playing it requires the use of both hands, both feet and both knees. In addition there is no tactile sensation in your hands to tell you where you are on the neck so it uses visual markers.

This is one instrument where you have to watch your hands, and you also have to listen very carefully to what you are doing to make sure your intonation is correct. In country music circles where it is commercially used, this is considered to be the instrument that separates the men from the boys.