Isn't it great that we live in a world where anything could be a cause for celebration? For those of you wondering, July 5th happens to be the official birthday of the summer must-have: the bikini. Introduced by French designer Louis Réardon in 1946, it's hard to imagine what the past 66 years would have been like without the iconic two-piece. See if you can recognize some of history's most iconic "bikini moments" below (via Huffington Post):

Rita Hayworth, 1941

Ava Gardner, 1944

Barbara Stanwyck, 1944

Virginia Mayo, 1944

Barbara Laage, 1946

Marilyn Monroe, 1951

Jayne Mansfield, 1955

Elizabeth Taylor, 1959

Ursula Andress in "Dr. No," 1962

Raquel Welch, 1966

Phoebe Cates in "Fast Times at Ridgemont High," 1982

Carrie Fisher in "Star Wars Episode VI: Return of the Jedi," 1983

Tyra Banks for Sports Illustrated, 1997

Angelina Jolie in "Lara Croft: Tomb Raider," 2001

Halle Berry in "Die Another Day," 2002

Cameron Diaz & Demi Moore in "Charlie's Angels: Full Throttle," 2003 

Jessica Simpson in "These Boots Are Made For Walking," 2005

Jessica Alba in "Into The Blue," 2005

Pamela Anderson's Marriage to Kid Rock in 2006..

and again for PETA, 2008

Helen Mirren, 2008

Katy Perry in "California Gurls," 2010

Kate Upton for Sports Illustrated, 2012