What are some alternatives?
When comparing MkDocs and GitBook, you can also consider the following products
ReadTheDocs - Spend your time on writing high quality documentation, not on the tools to make your documentation work.
Atlassian Bitbucket Server - Atlassian Bitbucket Server is a scalable collaborative Git solution.
Sphinx Search - Sphinx is an open source full text search server, designed with performance, relevance (search quality), and integration simplicity in mind. Sphinx lets you either batch index and search data stored in files, an SQL database, NoSQL storage.
Visual Studio Team Services - Visual Studio Team Services (VSTS) provides unlimited Git hosting, cloud build for CI, agile planning and continuous delivery.
Daux.io - Daux.io is a documentation generator that uses a simple folder structure and Markdown files to...
GitHub Desktop - GitHub Desktop is a seamless way to contribute to projects on GitHub and GitHub Enterprise.