Start with the book: Designing Interactions, compiled and edited by Bill Moggridge, 2007. ACM has a special interest group, SIGCHI, on Computer Human Interact

Start with the book: Designing Interactions, compiled and edited by Bill Moggridge, 2007. ACM has a special interest group, SIGCHI, on Computer Human Interaction. They have online resources, local chapters, an annual conference https://www.acm.org/special-interest-groups/sigs/sigchi https://www.acm.org/special-interest-groups/sigs/sigchi Also an annual conference: https://sigchi.org/conferences/upcoming-conferences/ https://sigchi.org/conferences/upcoming-conferences/ If you have access to ACM's Digital Library, all of the Proceedings are there. Do searches for documentation for different systems. There is a NextStep manual on Archive.org, for example. There are Xerox PARC Altos manuals at bitsavers.org. There are X Windows docs at X.org.