Processing is a flexible software sketchbook and a language for learning how to code within the context of the visual arts.
Javascript implementation of processing, "reinterpreted for today's web"
openFrameworks is an open source C++ toolkit for creative coding
SuperCollider is a platform for audio synthesis and algorithmic composition, used by musicians, artists, and researchers working with sound.
Cinder is a free and open source library for professional-quality creative coding in C++.
The aim of the project is to create an easy to use, lightweight, 3D library with a default WebGL renderer. The library also provides Canvas 2D, SVG and CSS3D renderers in the examples.
Gibber is a live coding environment for the web browser, using the Gibberish.js audio engine, the CodeMirror code editor library and wrapping Three.js for 3d graphics and shader support. Version 2 of Gibber features a much more efficient audio engine, some interesting mapping abstractions and a server/database backend for publishing and browsing files and collaboratively live coding.
Tone.js is a framework for creating interactive music in the browser. It provides advanced scheduling capabilities, synths and effects, and intuitive musical abstractions built on top of the Web Audio API.