Stokes' Theorem is a fundamental principle in calculus that connects surface integrals and line integrals. It states that the integral of a vector field over a surface can be transformed into the integral of its curl over the boundary of that surface. This means that instead of calculating the entire surface, you can just focus on the edges, making complex problems easier to solve. In simpler terms, if you have a curved surface and you want to understand how a vector field behaves over it, Stokes' Theorem allows you to look at the flow along the boundary instead. This powerful relationship is widely used in physics and engineering, especially in fluid dynamics and electromagnetism.