Hair: The American Tribal Love-Rock Musical is a rock musical with a book and lyrics by James Rado and Gerome Ragni and music by Galt MacDermot. A product of the hippie counter-culture and sexual revolution of the 1960s, several of its songs became anthems of the anti-Vietnam War peace movement. The musical's profanity, its depiction of the use of illegal drugs, its treatment of sexuality, its irreverence for the American flag, and its nude scene caused much comment and controversy. The musical broke new ground in musical theatre by defining the genre of "rock musical", using a racially integrated cast, and inviting the audience onstage for a "Be-In" finale.

Hair tells the story of the "tribe", a group of politically active, long-haired hippies of the "Age of Aquarius" living a bohemian life in New York City and fighting against conscription into the Vietnam War. Claude, his good friend Berger, their roommate Sheila and their friends struggle to balance their young lives, loves and the sexual revolution with their rebellion against the war and their conservative parents and society. Ultimately, Claude must decide whether to resist the draft as his friends have done, or to succumb to the pressures of his parents (and conservative America) to serve in Vietnam, compromising his pacifistic principles and risking his life.

David Michael Letterman (born April 12, 1947) is an American television host and comedian. He hosts the late night television talk show, Late Show with David Letterman, broadcast on CBS. Letterman has been a fixture on late night television since the 1982 debut of Late Night with David Letterman on NBC. Letterman recently surpassed friend and mentor Johnny Carson for having the longest late-night hosting career in the United States of America.

Letterman is also a television and film producer. His company Worldwide Pants produces his show as well as its network follow-up The Late Late Show with Craig Ferguson. Worldwide Pants has also produced several prime-time comedies, the most successful of which was Everybody Loves Raymond, currently in syndication.

In 1996, David Letterman was ranked #45 on TV Guide's 50 Greatest TV Stars of All Time.

Letterman was born in Indianapolis, Indiana. His father, Harry Joseph Letterman (April 1915 – February 1973), was a florist of British descent; his mother Dorothy Letterman (née Hofert, now Dorothy Mengering), a Presbyterian church secretary of German descent, is an occasional figure on the show, usually at holidays and birthdays.