The painting technique that uses water-based paint applied to a wet surface is called "fresco." In this method, pigments mixed with water are applied to freshly laid wet plaster. As the plaster dries, the paint becomes an integral part of the wall surface. This technique was widely used during the Renaissance, with famous examples found in the Sistine Chapel, where Michelangelo created incredible works. Frescoes are valued for their durability and vibrant colors, although they require skill and speed to execute correctly, as the artist must work quickly before the plaster sets.