"Southern Harmony and Musical Companion" is a shape note hymnbook first published in 1835 by William Walker. It was designed to facilitate singing in religious gatherings, particularly in the Southern United States. The book features a unique notation system that uses shapes to represent different musical notes, making it easier for people to learn and sing hymns. The collection includes a variety of hymns, spirituals, and folk songs, reflecting the musical traditions of the time. It played a significant role in the development of shape note singing and has influenced many communities and singing schools throughout the years.