A Pixel Shader is a type of computer program used in graphics processing to determine the color and brightness of individual pixels on the screen. It plays a crucial role in rendering images by applying effects like lighting, shadows, and textures. This allows for more realistic visuals in video games and other graphic applications, enhancing the overall experience for users. In modern graphics, Pixel Shaders are part of the larger Graphics Processing Unit (GPU) architecture. They work alongside other shaders, such as Vertex Shaders, to create detailed and dynamic scenes. By manipulating pixel data, these shaders help bring life to characters and environments, making them more engaging and visually appealing.