From some brief playing around, it's a web-based development environment: 1. At the simplest level, it's an installation of Ace (http://ace.c9.io/ http://ace.c

From some brief playing around, it's a web-based development environment: 1. At the simplest level, it's an installation of Ace (http://ace.c9.io/ http://ace.c9.io/), an in-browser code editor. So you can edit code in-browser and it gets saved it to some (free) cloud storage. 2. There are some social features added on to this, which I haven't really investigated, but I guess you can form groups, get a feed of updates, share projects, etc. 3. In addition to the basic cloud storage + editing, you can spin up (also free) VM instances to back the editor, forming a dev environment. Your web-based editing space gets mounted as /home, and you have root access to an Ubuntu machine so you can install whatever you need. This can all be managed through either the web interface, or SSH if you prefer. However since they're only intended to back the IDE, the VMs shut down about 20 mins after everyone accessing one has closed their Koding browser window, to discourage using them as free VPS hosting. There are a few other companies in this space. Cloud9, which developed the Ace editor (https://c9.io/ https://c9.io/) are possibly the best-established. Koding seems to differentiate by emphasizing the social/collaborative features more, and possibly in being more generous with the VMs. There is also https://www.nitrous.io https://www.nitrous.io, which I don't know anything about. If anyone's up for writing an article, I'd certainly be interested in an overview of the current offerings from someone who's actually used them, i.e. more in-depth than I can glean from checking out their websites.