Her face is everywhere, from backpacks to refrigerator magnets. She occasionally sports a mustache and glasses, and her head has even been replaced by Bart Simpson’s! But make no mistake, thousands of people a year crowd around the real thing hanging in the Louvre in Paris. So, what is it all about, exactly? What makes the Mona Lisa such an enduring image, recognizable by millions of people around the world? The Mona Lisa was painted by Leonardo da Vinci between 1503 and 1507. The painting itself, oil on panel, is quite small: 30 x 21 inches. It is has been stolen and returned, appears to have had part of it cut away, and depicts a Florentine noblewoman against an enigmatic background. It is likely a portrait of a Florentine woman named Lisa Gherardini.

Spend some time looking at the painting, at Lisa’s cool expression as she stares out of the frame with her arms delicately crossed. What is she thinking? Is she pleased? Sure of herself? Shy? A small smile appears to be creeping up one side of her mouth and her eyes seem to shift to the right. Is Lisa playing coy?

Leonardo da Vinci used a technique called sfumato, which means “smoky” in Italian, and he applied sfumato techniques to the corners of the Mona Lisa’s eyes and her mouth, creating the famous ambiguity of personality. Because of this, Lisa’s mood seems to change upon every viewing, and sometimes it feels like she’s in on the joke. Sfumato also helps add to the realism of the portrait, making Mona Lisa appear to live and breathe.

When we look at the Mona Lisa, we are as close as we can get to the genius of Leonardo da Vinci. At some point in history, he sat in a room with this woman, mere feet apart, and painted her from life. The painting is a virtuoso work, an example of da Vinci’s immense skill, and an enduring masterpiece.