From Wikipedia
The Private Life Of A Masterpiece

The Art of Painting

Also known as The Allegory of Painting, or Painter in his Studio, is a famous 17th century oil on canvas painting by Dutch painter, Johannes Vermeer. Many art experts believe that the work of art is an allegory of painting, hence the alternate title of the painting. It is the largest and most complex of all of Vermeer's works.
The painting is famous for being one of Vermeer's favourites, and is also a fine example of the optical style of painting. Created in an age without photography, it offers a realistic visual depiction of the scene. The use of bright colours, and the impact of light streaming through the windows on various elements of the painting, are other highlights.