According to HowStuffWorks, a graphics card translates the pixels from video data into images seen on the screen. The central processing unit sends information regarding the image to the graphics card. The card then figures out how to use the pixels to form that image. From there, the information is sent through a cable to the computer monitor or laptop screen.
As an article from the Houston Chronicle describes, video data is turned into high-quality video thanks to a graphics card. About the size of a 3-by-5 card, this set of chips converts video data from the computer's processor into signals from the monitor. Four parts are used by the graphics card to accomplish these tasks: a motherboard, a processor, memory for holding information about each pixel and a monitor. The processor of a graphics card is called a graphics processing unit (GPU). This GPU specifically performs calculations that help create the graphics. Upgraded graphics cards can be purchased and installed for faster processing and higher-quality images. Computer gamers and those who work with 3-D graphics often may find upgrading their graphics cards useful. Upgraded cards tend to have a higher frames per second rate, more memory and a faster processor.