Low-level graphics refer to the basic techniques used to create images and visual effects in computer programs. This involves directly manipulating pixels on the screen, which allows for precise control over how graphics are rendered. Programmers often use low-level graphics when they need to optimize performance or create custom visual effects that higher-level tools may not support. In contrast to high-level graphics libraries, which provide ready-made functions and tools, low-level graphics require a deeper understanding of how computers process images. This approach is commonly used in game development, where developers like John Carmack have pushed the boundaries of what is possible in real-time rendering.