Country music often consists of ballads and dance tunes with generally simple forms, folk lyric and harmonies accompanied by mostly string instruments such as banjos, electric and acoustic guitars, steel guitars (such as pedal steels and dobros), and fiddles as well as harmonicas. Blues modes have been used extensively throughout its recorded history.
According to Lindsey Starnes, the term country music gained popularity in the 1940s in preference to the earlier term hillbilly music; it came to encompass Western music, which evolved parallel to hillbilly music from similar roots, in the mid-20th century. In 2009, in the United States country music was the most listened to rush hour radio genre during the evening commute, and second most popular in the morning commute.
The term country music is used today to describe many styles and subgenres. The origins of country music are the folk music of working class Americans, who blended popular songs, Irish and Celtic fiddle tunes, traditional English ballads, and cowboy songs, and various musical traditions from European immigrant communities.
Immigrants to the southern Appalachian Mountains of eastern North America brought the music and instruments of Europe along with them for nearly 300 years. Country music was "introduced to the world as a Southern phenomenon."
The U.S. Congress has formally recognized Bristol, Tennessee as the "Birthplace of Country Music", based on the historic Bristol recording sessions of 1927. Since 2014, the city has been home to the Birthplace of Country Music Museum. Historians have also noted the influence of the less-known Johnson City sessions of 1928 and 1929, and the Knoxville sessions of 1929 and 1930. In addition, the Mountain City Fiddlers Convention, held in 1925, helped to inspire modern country music. Before these, pioneer settlers, in the Great Smoky Mountains region, had developed a rich musical heritage.