gc.js or gameCanvas.js is a lightweight javascript library. The library is built on the Canvas API and makes it a lot easier to create and draw to the HTML Canvas.
Website: https://aaserver.net/libraries/gameCanvas
You can read the documentation for gc.js under wiki, then press documentation in the sidebar
You can contribute to this project by adding new functions, updating documentation or fixing bugs. Just create a pull request and I will merge it if I think it should by included and your name will be added to a contributor list (Not created yet)