io.js is a fork of Joyent’s Node.js which is totally compatible with node.js, that is run by some of the same maintainers of Node.js. It was first published on January 2015 and is used for developing applications that make heavy use of the ability to run JavaScript both on the client, as well as on server side and therefore benefit from the re-usability of code and the lack of context switching. It provides faster, community driven development and compatibility with node.js.