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