GitHub is a web-based Git repository hosting service that offers version control and source code management like Git but with additional features like a graphical interface and collaboration tools. It allows both registered and non-registered users to browse public repositories. While GitHub's open source projects are not required to meet the Open Source Definition, users should check the license in each repository to determine if it meets their needs. GitHub also offers a private enterprise version designed for large companies to host code behind a firewall. Originally self-funded, GitHub received $100 million in venture capital in 2012, four years after being founded.