In computer graphics, a Boolean is a compound object that combines two objects, called operands. It is used in modeling to join objects seamlessly and to cut holes. There are three operations: union, intersection, and subtraction. Union merges the two objects into one continuous surface. Intersection creates an object from the overlapping volumes of the two operands. Subtraction, or difference, is the most common operation: one operand is a tool to cut a hole in the other operand.