— Free Encyclopedia of Human-Computer Interaction — Encyclopedia of Human-Computer Interaction

Great resource with 25 different chapters so far ranging on topics such as User Experience and Experience Design, End-User Development and Semiotics.

Quotable from the Website: “We’re on a mission to make free and open educational materials: There are so many great minds in the Human-Computer Interaction and Interaction Design community and we want to empower these authors to reach all their interested readers around the world. We believe these authors have the minds to change the world and deserve a publishing venue truly designed for the author and the reader, not the publisher and the profit.”