the.com/steel guitar

means A guitar played horizontally with a metal bar or slide pressed against the strings instead of fingers fretting them, producing that smooth, bending, crying tone heard in country, Hawaiian, and blues music.

from Traces back to Hawaii in the late 1800s, where a player (legend credits a young Joseph Kekuku) ran a piece of metal or a comb along the strings of a regular guitar, discovering the sliding, wailing sound. The technique spread to the mainland US, where it merged with country music and eventually got mounted on legs with pedals and extra strings, becoming the pedal steel. The name 'steel' comes simply from the steel bar used to fret the strings — no fingers, no frets, just slide.