Rallax.js is a vanilla JS plugin that implements a dynamic parallax scrolling effect, without relying on dependencies like jQuery. It makes easy to create a parallax effect on a target HTML element, with great performance and a robust API. Make either a basic scrolling parallax, or change it up with automatic callbacks (when method), start/stop, speed changes, and mobile handling. Developed by GitHub user Christopher Cavalea (ChrisCavs), licensed under the MIT license.