Hyrax is a frontend of Hydra with CMS and social features. It's a merger of https://github.com/projecthydra/sufia and https://github.com/projecthydra/curation_concerns
Hydra is a web applications framework based on the digital asset management repository (Fedora) and the search index (Solr). Demos: https://projecthydra.org/apps-demos-2-2/
Fedora stands for Flexible Extensible Digital Object Repository Architecture. Its repository is based on the Linked Data Platform (5-star linked data according to Tim Berners-Lee http://5stardata.info/en/). An intro presentation: http://fedorarepository.org/presentations.
In regard to the name:
In 1997 a research project at Cornell University was named the Flexibile Extensible Digital Object Repository Architecture (Fedora). In 1998 the Fedora name was used in article published by Payette and Lagoze and in research software that was released to the public under the Fedora name.
In 2005 Red Hat, Inc. filed a trademark request for the name "Fedora" to be associated with their Linux operating system project. Cornell and UVA formally disputed the request and, as a final settlement, all parties settled on a co-existence agreement [...]