Multivariable Integration is a mathematical technique used to calculate the integral of functions with more than one variable, such as x and y. This process extends the concept of single-variable integration to higher dimensions, allowing us to find areas, volumes, and other quantities in 2D and 3D spaces. In multivariable calculus, integrals can be evaluated over regions defined in Cartesian or polar coordinates. Techniques like double integrals and triple integrals are commonly used, enabling the computation of complex shapes and surfaces by summing infinitesimal contributions across the entire region of interest.