Surface modeling is a technique used in computer-aided design (CAD) to create a 3D representation of an object. It focuses on defining the outer shape or surface of an object rather than its internal structure. This method is particularly useful for designing complex shapes, such as those found in automotive and aerospace industries, where aesthetics and aerodynamics are crucial. In surface modeling, designers use mathematical equations and curves to define surfaces. Tools like NURBS (Non-Uniform Rational B-Splines) allow for precise control over the shape and smoothness of the surfaces. This approach enables the creation of intricate designs that can be easily modified and refined during the design process.