GLSL

High-level shading language for graphics programming, used with OpenGL and Vulkan to define vertex and fragment shaders that run on the GPU. Provides C-like syntax with built-in vector and matrix types, making it the standard way to program programmable pipeline stages in real-time 3D rendering.

Maintained by the Khronos Group and supported directly by OpenGL without extensions. GLSL shares version alignment with OpenGL and feeds into SPIR-V for Vulkan toolchains. The specification and extension sources live in the KhronosGroup repository, with glslang serving as the reference compiler front-end for validation.

Key features:

• Vertex and fragment shader programs with C-like syntax
• Native vector and matrix types, built-in math and texture sampling functions
• Version progression from 1.10 through 4.60, aligned with OpenGL releases
• Compute shader support in recent versions for general-purpose GPU work
• Cross-platform use via OpenGL, WebGL, and Vulkan pipelines

GLSL is the language of choice for real-time 3D graphics in games and applications, WebGL content in browsers, creative coding and generative art, and post-processing effects. Developers integrate it through graphics APIs, shader editors, and tools like Three.js, Shadertoy, or native engine pipelines.