The function "dblquad" is part of the scipy library in Python, specifically designed for performing double integration. It allows users to compute the integral of a function over a two-dimensional area, making it useful for various applications in science and engineering. The function takes as input the integrand, the limits of integration for both variables, and additional parameters if needed. To use "dblquad," you define the function to be integrated and specify the bounds for each variable. The function then returns the computed integral value along with an estimate of the error. This makes "dblquad" a powerful tool for numerical integration in multidimensional spaces.