Subhub is a free Chrome add-on developed by Barnaby Malet. It falls under the category of Browsers and is classified as an Add-ons & Tools subcategory. The main purpose of Subhub is to add an "Open in Sublime" button to GitHub.

To use Subhub, you need to have OSX, Sublime Text 3, and the accompanying Sublime plugin installed on your system. Once installed, Subhub adds a convenient button to GitHub, allowing you to quickly open any file in Sublime Text for editing.

This feature can be particularly useful for developers who prefer Sublime Text as their code editor. With Subhub, you can seamlessly switch between browsing and editing code on GitHub without any hassle.