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Atlas is a wiki-like, git-managed authoring platform for creating books. http://chimera.labs.oreilly.com/books/1230000000065/ch01.html
Some of the features of Atlas are as follows:
- Simple markup = Atlas supports AsciiDoc and, for simpler projects, Markdown.
- Git backend = If you have a book, you have a git repository and all of the power and convenience that comes with using git version control.
- Easy book, ebook, and web builds = Atlas lets you build your project in four formats at any time: Mobi (for the Kindle), EPUB (for most other ebook platforms), PDF (for print), and HTML (for the web). Atlas also gives you tools to debug your ebook formats so that you can identify and fix problems quickly.
- An invitation system = Add collaborators to your project at any time by simply sending an invite.
- Flexible writing options = You can write directly within Atlas, but if writing in a web browser is not for you, no problem. Just use git to clone your book to a local machine and write in the text editor of your choice.