A relief sculpture is partially carved out of or into a flat base, the two-dimensional surface. There are three types of relief sculpture: alto (high), bas (low) and sunken. An alto relief means that the sculpture protrudes greatly from the flat plane and could almost stand alone as a sculpture if the base were removed. In bas, the sculpture protrudes only slightly above the plane. In sunken, the carving juts into the base, seen as an indentation.
Sculpto-painting is an art form that combines the techniques of painting and sculpting, the results of which can be considered two-dimensional sculpture. Sculptopaintings share many characteristics with relief sculpture, but include the addition of pigments to the sculpture. The term was first used to describe the work of Ukrainian-born sculptor Alexander Archipenko, for his work "Espanola (Still Life with Head)" in 1906.
A new creative concept of "two-dimensional sculpture" is emerging in the art world: drawings, sketches or outlines of figures that would be three-dimensional if they were generated in the real world, but instead are represented on two-dimensional media, such as canvas, paper or computer screens. Mike Mission is a pioneer of "two-dimensional sculpture." This is how he describes his art: "The artwork presented on this site is the product of conceptual research entitled 'two-dimensional sculpture.' This concept is founded on an idea of replacing the most appealing of angles from any point of view of any given three-dimensional sculpture with the ideal single one. This ideal point of view then levels these purely imagined sculptures into two dimensions." The result are two-dimensional illustrations that depict three-dimensional sculptural forms.
Three-dimensional sculptures make up the majority of sculptures we see in the world of art. A three-dimensional sculpture must be able to stand on its own; otherwise, it is considered a relief. Familiar sculptures include Frederic-Auguste Bartholdi's "Statue of Liberty," Auguste Rodin's "The Thinker" and Michelangelo's "David." These are all traditional 3-D sculptures. Some nontraditional modern sculptures include Salvador Dali's "Lobster Telephone" and Sol LeWitt's "Open Geometric Structure." Three-dimensional sculptures may be abstract, kinetic, classical or even created from "found objects." Nearly every piece of art that is three-dimensional is considered sculpture.