OpenGL is a cross-platform graphics API (Application Programming Interface) used for rendering 2D and 3D graphics. It provides a set of functions that allow developers to create visual content in applications, such as video games and simulations. By using OpenGL, programmers can control the graphics hardware directly, enabling efficient rendering of complex scenes. Originally developed by Silicon Graphics, Inc. in the early 1990s, OpenGL has become a standard in the graphics industry. It is widely supported across various operating systems, including Windows, macOS, and Linux. This versatility makes it a popular choice for developers looking to create high-performance graphics applications.