Three.js is a JavaScript 3D library that allows developers to create interactive 3D graphics and animations that are fully compatible with modern web browsers. It is the most widely used 3D library and is used by developers to create cutting-edge 3D experiences for the web. Through its intuitive API, Three.js enables developers to quickly create complex 3D scenes, including all the different types of lights, materials, textures, and shapes. It also provides features like physics-based collisions, advanced GPU-based post-processing effects, and support for VR and AR devices. The Three.js library also comes with a vibrant community, extensive learning resources and a range of merchandise that celebrates the best in 3D design and development. With Three.js, developers have the perfect toolkit to create stunning 3D experiences for the web.