Introduction Portrait painting has been an important art form since the times of Ancient Egypt, when artists would make portraits of their pharaohs and other important people. Portraits were also widely used during the Renaissance, when many great works of art were produced, including stunning pieces like Leonardo da Vinci’s Mona Lisa and Michelangelo’s David. Today, portraiture is still popular and can be found in museums all over the world, as well as on everyday objects like money and coins. [...]