OpenGL vs WebGL: What are the differences?

OpenGL: An environment for developing 2D and 3D graphics applications. It is a cross-language, cross-platform application programming interface for rendering 2D and 3D vector graphics. The API is typically used to interact with a graphics processing unit, to achieve hardware-accelerated rendering; WebGL: A JavaScript API for rendering 3D graphics within any compatible web browser. It is integrated completely into all the web standards of the browser allowing GPU accelerated usage of physics and image processing and effects as part of the web page canvas. Its elements can be mixed with other HTML elements.

OpenGL belongs to "Graphics Libraries" category of the tech stack, while WebGL can be primarily classified under "Javascript UI Libraries".