Hip hop music, also called hip-hop or rap music, is a music genre developed in the United States by inner-city African Americans in the 1970s which consists of a stylized rhythmic music that commonly accompanies rapping, a rhythmic and rhyming speech that is chanted. It developed as part of hip hop culture, a subculture defined by four key stylistic elements: MCing/rapping, DJing/scratching with turntables, break dancing, and graffiti writing. Other elements include sampling beats or bass lines from records, and rhythmic beatboxing. While often used to refer solely to rapping, "hip hop" more properly denotes the practice of the entire subculture. The term hip hop music is sometimes used synonymously with the term rap music, though rapping is not a required component of hip hop music; the genre may also incorporate other elements of hip hop culture, including DJing, turntablism, scratching, beatboxing, and instrumental tracks.