Apparently, Apple has been slowly reducing the number of GPL licensed applications that are bundled with OS X. I’m not surprised by this news, especially considering that FreeBSD is doing the same thing. However, buried in the conversation on Hacker News was an interesting comment, that most, if not all, of the top projects on Github are either BSD or MIT licensed. My curiosity was piqued, this was too good to pass up.

Github has a handy page which ranks the most popular watched repositories. The projects listed range from the Linux kernel itself to CSS frameworks, and everything in between. Github also has a “Popular Forked” page, which lists the repositories that have been forked the greatest number of times, and an “Interesting” page, which I believe to be a combination of the two. (If I’m wrong about this, please let me know in the comments.) The breakdown of the projects and their associated licenses, as of February 2012, looks like this:

MIT License

• Ruby on Rails
• Impress.js
• Devise
• Three.js
• Express
• Jekyll
• Chosen
• Socket.io
• Paperclip
• Formtastic
• Authlogic
• Raphael
• Cucumber
• Cancan
• Janus
• Foundation
• Node.js
• BackBone
• CoffeeScript
• Underscore
• Symfony
• Resque
• Compass
• will_paginate
• Sinatra

BSD Style

• Blueprint CSS
• Redis
• Termkit
• D3
• Django
• git-flow
• asi-http-request

Apache License v2.0

• Twitter Bootstrap
• Three20
• Less.js
• Facebook PHP SDK
• Tornado

Dual GPL and MIT

• jQuery
• jQuery Mobile
• jQuery UI

No License Listed

• Homebrew
• Oh-my-zsh
• Gitignore

I could not find a license on these three projects, if I missed it, please let me know in the comments. – Thanks!

Public Domain

• HTML 5 Boilerplate
• Normalize.css

GNU-AGPL v3

• Diaspora

PHP and Zend

• HipHop

Dual BSD and MIT

• Modernizr

GPL

• Linux

If we move this list into a graph, the result looks like this:

From this view, it is clear that MIT is the dominant license among the most popular projects on Github. MIT is followed, at a distance, by BSD and Apache. The JQuery libraries are available in a dual GPL/MIT license, depending on what the developers needs are. Only the Linux kernel is licensed under pure GPL. It would be easy to assume that this list shows a trend away from the GPL and towards the more open and free MIT/BSD style licenses, however, that logical leap would be foolish considering the projects listed.

If, instead of counting the number of projects listed, we weighed each project by its impact on the world, the resulting graph might look more like this:

The impact of the Linux kernel on the computing industry is hard to overestimate. The year of the Linux Desktop may never come, but Linux dominates in the data center, especially in web hosting data centers that many of the smaller projects listed above rely on. Linux is the foundation that allows most of the other projects to exist.

What I am interested in is if the popularity of the BSD and MIT licenses is actually due to the simplicity of the license. They are short, easy to understand, and impose no real restrictions on the use of the code. Has the GPL become too complicated for its own good? I’m looking forward to the conversation.