Stands for "Computer-Aided Design." CAD is the use of computers to create 2D and 3D designs. Common types of CAD include two-dimensional layout design and three-dimensional modeling.
2D CAD has many applications, but it is commonly used to design vector-based layouts. For example, architects may use CAD software to create overhead views of building floor plans and outdoor landscapes. These layouts, which contain vector graphics, can be scaled to different sizes, which may be used for proposals or blueprints. 2D CAD also includes drawings, such as sketches and mockups, which are common at the beginning of the design process.
3D CAD is commonly used in developing video games and animated films. It also has several real-world applications, such as product design, civil engineering, and simulation modeling. 3D CAD includes computer-aided manufacturing (CAM), which involves the actual manufacturing of three-dimensional objects.
Like 2D CAD drawings, 3D models are typically vector-based, but the vectors include three dimensions, rather than two. This allows designers to create complex 3D shapes that can be moved, rotated, enlarged, and modified. Some 3D models are created exclusively of polygons, while others may include Bézier curves and other rounded surfaces.
When creating a 3D model, a CAD designer may first construct the basic shape of the object, or "wireframe." Once the shape is complete, surfaces can be added that may include colors, gradients, or designs that can be applied using a process called texture mapping. Many CAD programs include the ability to adjust lighting, which affects the shadows and reflections of the object. Some programs also include a timeline that can be used to create 3D animations.