Delta blues is a music genre that originated in the early 20th century in the Mississippi Delta, a region in the southern United States. It is characterized by its expressive guitar playing, soulful vocals, and themes of hardship, love, and life struggles. The music often features a simple structure, typically using a twelve-bar blues format. Key instruments in Delta blues include the acoustic guitar and harmonica, with artists often performing solo. Notable musicians associated with this style include Robert Johnson and Muddy Waters. Delta blues has significantly influenced many other genres, including rock and roll and rhythm and blues.