Web-Based Code Editor By Adobe – Brackets

Brackets is an open source code editor (IDE), built by Adobe, which is created with only client-side web technologies like HTML-CSS and JavaScript.

The editor focuses on simplicity and, rather than too many panels, the quick-edit UI is the main thing.

A "live development" feature syncs a browser with the editor and displays any changes instantly.

It is integrated with the Chrome's Developer Tools and JSLint for debugging.

Brackets, although being web-based, works in a native shell (Win & Mac versions available) to reach the filesystem.