Foam board,also known as foam core or foam core, is a kind of backing material widely used in frame art. It is made from a foam polystyrene foam covered with paper or plastic,so foam is at the heart of the sandwich. This material is usually white, although some manufacturers also offer black. Thickness is 1/8 or 3/16 inches. 

This material is light and sturdy, which makes it an ideal frame for large artwork or posters because it is too small for the overall work. Its rigidity stabilizes the art of paper, but it's worth noting that it's not really a file. Styrofoam break down over a long period of time, and the by-product of this decomposition may be acidic and may accelerate the aging of the artwork it uses. The foam board can be purchased in very large sheets, which leads to its second most common use as a display board for school projects and science exhibitions. Three large planks can be connected with white artist tape, which can be made into a triple or triple display.