The Blues is a musical genre that was born in the African American communities of the United States at the end of the 19th century. It is characterized by the use of specific musical patterns, such as the twelve-bar blues form, and by emotionally charged lyrics that often deal with themes such as sadness, love, and the difficulties of life. The Blues have deeply influenced the evolution of other musical genres, such as jazz and Rock 'n' Roll, and remain a popular and powerful means of expression today.