The Holmes Brothers

Blues is an African American musical tradition defined by expressive "blue notes," call-and-response phrasing, and a characteristic use of dominant-seventh harmony in cyclical song forms (most famously the 12‑bar blues). It is as much a feeling as a form, conveying sorrow, resilience, humor, and hard-won joy. Musically, blues commonly employs the I–IV–V progression, swung or shuffled rhythms, and the AAB lyric stanza. Melodies lean on the minor/major third ambiguity and the flattened fifth and seventh degrees. Core instruments include voice, guitar (acoustic or electric), harmonica, piano, bass, and drums, with slide guitar, bends, and vocal melismas as signature techniques. Over time the blues has diversified into regional and stylistic currents—Delta and Piedmont country blues, urban Chicago and Texas blues, West Coast jump and boogie-woogie—while profoundly shaping jazz, rhythm & blues, rock and roll, soul, funk, and much of modern popular music.