Video card
In early computing years, graphics processing was very basic and could be done by the CPU along with all the other processing. However, as computer games advanced and started using 3D graphics, the CPU had too much to do and CPU-makers could not keep up on making them faster.  Eventually, video cards, with their own GPU, were invented to solve this problem.  This lets the CPU do more of its own work since it does not have to spend any time on advanced graphics calculations; it can simply pass these calculations off to the GPU to be done.