What do graphics cards actually do?

Question

Yeah, I know they help play games with good FPS and used with workstations, But how do they actually accomplish that? What other purposes do they have.

Answer 1

Graphics cards are what puts the video on your screen with out some kind of graphics card you would not be able to have a picture on your monitor the card takes the data from the computer and translate it into the video that is displayed and that is the only purpose of a graphics card  

Answer 2

their purpose is to assist the cpu in calculating codes for graphics. In a software, there are hidden codes that the cpu calculates, at the same time, it must incorporate those calculations into graphical interface for the user to see. It must calculate the codes that incorporates the hidden calculations to user interface. with a graphics card, the cpu only has to do the hidden calculations, and the graphics card handle the incorporating and calculating the codes for incorporating, and then displaying.