7 things you may not know about the 'Mona Lisa'

There's a great deal of speculation about the person Leonardo da Vinci painted at the beginning of the 16th century. One theory goes that both a man and a woman modeled for the portrait. But a more widely recognized interpretation is that Mona Lisa was Lisa del Giocondo, the wife of a Florentine silk trader.

The painting landed in the private collections of French kings following Leonardo da Vinci death's in 1519. Following the French Revolution, it held a place of honor in Napoleon Bonaparte's bedroom. As of 1815, it could be seen by the public in the Louvre Museum in Paris.

The twin has been on show for some time in Madrid's Museo del Prado. In 2012, it was discovered that this painting was created simultaneously with the original. Restoration work exposed the same Italian landscape in the background and the same improvements. That proves that both works were created at the same time. The painter of this one was presumably Francesco Melzi, one of da Vinci's pupils.

The "Mona Lisa" didn't really become famous until she disappeared. An Italian living in Paris stole the painting from the Louvre in 1911, wishing to take it back to Italy. It remained missing for two years before police arrested the man. The painting's return to Paris prompted an unprecedented storm of visitors to the Louvre.

Mona Lisa evokes a lot of different feelings – and apparently not only positive ones. Two different acts of vandalism were performed on the painting in 1956. One vandal threw acid at the painting, damaging it. Then a Bolivian tourist threw a rock at it. Since then, it's protected behind bullet-proof glass, which shielded it when a visitor threw a mug at it in 2009.

Countless scientists and art historians have analyzed the painting, unearthing surprising findings. In 2008, the mystery behind Mona Lisa's enigmatic smile was solved: a painting technique called "sfumato." Da Vinci applied several thin layers of paint over one another to create a blurred effect and blend the colors. It lends the painting, particularly the face, a rich, yet elusive atmosphere.

The "Mona Lisa" has not only prompted the greatest commentary ever in the history of art, it has inspired countless artists to create variations on it – from Joseph Beuys to Andy Warhol. As a media icon of the 20th century, she is found in everything from literature to music and advertising. Bob Dylan once said "Mona Lisa must have had the highway blues; you can tell by the way she smiles."