High-Level Shading Language (HLSL) is a programming language developed by Microsoft for writing shaders, which are programs that determine how graphics are rendered on the screen. HLSL is primarily used in DirectX, a set of application programming interfaces (APIs) for handling tasks related to multimedia, especially game development. It allows developers to create complex visual effects and manipulate graphics hardware efficiently. HLSL enables programmers to write code that runs on the GPU (Graphics Processing Unit), allowing for parallel processing of graphics tasks. This results in improved performance and visual quality in applications such as video games and simulations. HLSL supports various shader types, including vertex shaders and pixel shaders, to control different stages of the rendering pipeline.