Integration is a mathematical technique used to find the integral of a function. It is one of the two fundamental operations of calculus, the other being differentiation. Integration is used to calculate areas, volumes, and their generalizations. It is a way of adding slices to find the whole. The integral is the continuous analog of a sum. The symbol for "Integral" is a stylish "S". The integration is the process of finding the antiderivative of a function. The integration is the inverse process of differentiation. The integration denotes the summation of discrete data. In calculus, the idea of limit is used where algebra and geometry are implemented. Integration is used to find many useful quantities such as areas, volumes, displacement, etc. . The basic idea of integral calculus is finding the area under a curve. To find it exactly, we can divide the area into infinite rectangles of infinitely small width and sum. The definite integral is equal to g(b) − g(a), where Dg(x) = f(x) . There are several techniques of integration that involve classifying the functions according to which types of manipulations will change the function into a form the antiderivative of which can be more easily recognized. One useful aid for integration is the theorem known as integration by parts.