"Mona Lisa" is a painting from the Renaissance period. The author is the painter Leonardo da Vinci. This painting is his representative work. A portrait painting can be said to be one of the most famous oil paintings in the world. Few other works can be observed, researched or quoted as often as it is. Its holding country, the French government kept it in the Louvre in Paris for public appreciation. It was painted directly on aspen wood, with a small area, 77 cm long and 53 cm wide. The painting depicts a slightly smiling lady with introverted expression. Her smile is sometimes referred to as a "mysterious smile".