Bob Dylan (born Robert Allen Zimmerman, May 24, 1941) is an American singer-songwriter, author and visual artist. Widely regarded as the greatest songwriter of all time, Dylan has been a major figure in popular culture for more than 50 years. Much of his most celebrated work dates from the 1960s, when songs such as "Blowin' in the Wind" (1963) and "The Times They Are a-Changin'" (1964) became anthems for the civil rights and anti-war movements. His lyrics during this period incorporated a range of political, social, philosophical, and literary influences, defied pop music conventions and appealed to the burgeoning counterculture.