A graphics card, also known as a GPU (Graphics Processing Unit), is responsible for rendering images, videos, and animations on your computer's display. It handles complex calculations and processing tasks related to graphics and visual output, offloading this work from the CPU (Central Processing Unit). This results in smoother performance in graphics-intensive applications like video games, graphic design software, and video playback. Additionally, a graphics card can support higher resolutions and multiple monitors, enhancing the overall visual experience.