A musical genre combining elements of folk music and rock music.

In its earliest and narrowest sense, the term referred to a genre that arose in the USA and Canada around the mid-1960s. The sound was epitomised by tight vocal harmonies and a relatively unadorned approach to electric instruments as exemplified by the jangly sound of the Byrds' guitarist Roger McGuinn. The repertoire was drawn in part from folk sources, but even more from folk-influenced singer-songwriters such as Bob Dylan.

This original folk rock directly led to the distinct, eclectic style of British folk rock (aka electric folk) pioneered in the late 1960s by Pentangle and Fairport Convention. Starting from a North-American style folk rock, such bands deliberately incorporated elements of traditional British folk music. Fairport bassist Ashley Hutchings subsequently formed Steeleye Span in collaboration with traditionalist British folk musicians who wished to incorporate electrical amplification, and later overt rock elements, into their music.

This, in turn, spawned several other variants: the self-consciously English folk rock of the Albion Band and some of Ronnie Lane's solo work, and the more prolific current of Celtic rock, incorporating traditional music of Ireland, Scotland, Cornwall, and Brittany. Through at least the first half of the 1970s, Celtic rock held close to folk roots, with its repertoire drawing heavily on traditional Celtic fiddle and harp tunes and even traditional vocal styles, but making use of rock band levels of amplification and percussion.

In a broader sense, folk rock includes later similarly-inspired musical genres and movements. As with any genre, the borders are difficult to define. Folk rock may lean more toward folk or toward rock in its instrumentation, its playing and vocal style or its choice of material. While the original genre draws on music of Europe and North America, there is no clear delineation of which folk cultures music might be included as influences. However, the term is not usually applied to rock music rooted in the blues-based or other African American music (except as mediated through folk revivalists), nor to rock music with Cajun roots, nor to music (especially after about 1980) with non-European folk roots, which is more typically classified as world music.