Rockabilly is a style of music that was popular in the middle of the 20th century. It is attributed with playing an important role in the development of what we now call classic rock.
Rockabilly itself is a mixture of old American folk musics. At first, many people had difficulty classifying these kinds of songs. Even some of Elvis’s early work was doomed to this confusion. One of his first recordings didn’t receive any play on the radio because at the time many stations were segregated. The song in question sounded too country to be played on the black stations and too much like R&B to be played on the white stations. Of course this is old-fashioned fear. The day one DJ was brave enough to give the record a spin, it became wildly popular and helped set the stage for the desegregation of what gets played on the radio.
Rockabilly really became popular in the mid 1950s, and mostly died off shortly after. It’s had a handful of revivals and its influence can still be felt in many modern rock ‘n roll acts.