Gemini is both a document markup format and an internet protocol for accessing and downloading documents and other files.

The official project website is

Gemini (Document format)

The Gemini format is a plain-text format. The formatting is line-based and the documents are encoded using UTF-8.

Gemini (Network protocol)

The Gemini protocol is a simple network protocol that can be used to fetch files from servers.

Simplicity, or lack thereof

Most aspects of the protocol and the document format are very simple and easy to implement. Despite this, the protocol specification mandates the use of TLS, making stand-alone implementations very difficult. If one is okay with using an external library or wrapper to implement TLS, the rest of the protocol should be quite simple.

Relevant links