3D modeling is the process of creating mathematical representations of three-dimensional objects using specialized software. It is used widely in industries like architecture, engineering, medical, video games, and more. There are two main types of 3D models - solid models that represent an object's volume, and shell/boundary models that represent just the object's surface. Common modeling processes include using NURBS, polygons, primitives, and sculpting. Setting up an effective 3D scene also requires consideration. 3D modeling provides more flexibility and accurate photorealism compared to 2D modeling methods.