The steel guitar is an American country instrument that developed from guitars brought by Mexican cattlemen to Hawaii in the 1830s. The Hawaiians quickly adapted the instrument to suit their own music, tuning all the strings to the notes of a major triad. Joseph Kekuku is credited with developing a technique of using a comb to slide up and down the neck to create glissandi. To make this easier to do, the guitar was laid flat across the lap.
As the Hawaiian style of playing became more popular, the guitars were increasingly made in rectangular form and the comb was replaced with a steel bar. When they began to be manufactured commercially in the 1930s they acquired the name lap steel guitar.
Since the playing style of the lap steel limits the performer to a few keys, players began using instruments with more than one neck in order to increase the number of pitches available without having to retune. Having multiple sets of strings soon became cumbersome, however, and makers in the 1940s began fitting pedals that would simultaneously alter the tunings of a complete set of strings. For more on this, see pedal steel guitar.