Lily is an Open Source, browser-based visual programming language similar to Max, Pure Data or Vvvv that lets users create programs graphically by drawing connections between animation, data, images, sounds, text and graphics. Lily programs can be shared with other Lily users as JSON files, saved as Firefox add-ons or as XULRunner applications. Lily is written in Javascript and based on the Mozilla platform. It is distributed as a Firefox add-on.