A technique of decorating pottery in which the area of the figure is left empty (reserved) and the detail is painted in. The red of the clay would contrast with the black. It is an important phase in Greek vase painting, the inverse of black-figure style, and it started in Athens in the late 6th century BC and was popular to the 4th century BC. Other local schools also developed in the late 5th century, especially in southern Italy, and continued until c 300 BC. It was also produced at Corinth.