A graphics processing unit (GPU) is a processor that renders (or creates) images, animations, graphics and then displays them on the computer’s screen. A strong GPU is able to process complex animations and graphics smoothly and efficiently.
Images which GPUs calculate (render) may be 2D or 3D. For most applications, the GPU has to render two dimensional (2D) pictures. Modern GPUs are so powerful, that there is no difference in 2D performance between low-cost and expensive GPUs.
Some applications use 3D pictures to simulate three-dimensionality. Examples include video games, and applications for design and technical construction (CAD). The 3D acceleration performance of GPUs differs greatly. Generally, more expensive GPUs can render faster than low-cost ones.