Leonardo da Vinci’s 'Mona Lisa' is perhaps the most debated portrait in history. While most historians agree that the sitter is Lisa Gherardini, the wife of a Florentine silk merchant named Francesco del Giocondo, other theories have persisted for centuries. Some suggest she was a favorite mistress of the Medici family, or even a disguised self-portrait of Leonardo himself. The painting is famous for the 'sfumato' technique, which creates soft, hazy transitions between colors and tones, giving the subject her enigmatic smile and gaze that seems to follow the viewer. Leonardo never actually delivered the painting to the merchant who commissioned it; instead, he kept it with him for the rest of his life, continuously refining it. This obsession turned a simple portrait into a masterclass of psychological depth and technical perfection that continues to draw millions of visitors to the Louvre annually.