High Fidelity is open source software enabling shared virtual reality. Using High Fidelity, you can deploy a virtual reality server on a computer running Linux, OSX, or Windows, which can be then accessed by anyone from anywhere using our open source client. You can use the client with a regular 2D screen or with a head-mounted display (HMD) like the Oculus Rift or HTC Vive in conjunction with a mouse and keyboard and/or hand controllers to interact with your virtual environment. You can upload and manipulate your own content in many standard formats. You can also hyperlink your virtual spaces to other spaces, or browse a directory of publicly available servers run by other users. In addition to providing open source software, High Fidelity also offers services helping you to uniquely name virtual spaces, manage your identity in different virtual worlds, and exchange digital assets. We are also building a system for sharing excess server resources with other operators, allowing huge, high-capacity spaces to be created. Our mission is to create a viable set of open software and standards to make virtual reality happen on a global scale. For developers: Complex interactive content is created using JavaScript running on the client and/or server. Scripts can leverage the Bullet physics engine for fast accurate physics modeling. Content can be imported from FBX and OBJ formats. Both server and client currently run on OSX, Windows, and Linux. We use open standards and formats wherever possible. Our open source license is Apache 2.0. Contributions to development of the core systems can be made through our GitHub repository. Please dive in and enjoy and/or contribute to this forever in-progress reference, suggest edits, and let us know what we're missing.