Calculus is a branch of higher mathematics that is involved in calculating the areas and volumes of objects using integrals.

The basic applications of integration are in mathematics and physics. If the curved boundary of a plane region can be described in terms of functions, then the area enclosed by the figure and its perimeter can be expressed in terms of integrals. In three dimensions there are integrals for the volume and the surface area of a solid with a curved boundary. Integration can also be used to determine the mass of a body where the density of the matter inside it is allowed to vary from place to place.

If you can describe an object in terms of a function, then you can integrate it to calculate its surface area or its volume. Apparently, the Germans have found a mathematics function to describe Muslims:

Headline AP: Germany Takes Steps to Integrate Muslims