I need resources for information on the effects of the creation of GUIs for PCs. When I started looking up information on GUIs, but I mostly found the computers that first started using GUIs, the changes made in GUIs and how to make GUIs.
I'm doing an essay, and I need resources for some effects it had on people, and factual evidence to back up some of the statements. (statistics on users, effects on system response, effects on sales, etc.) Really, just something that would stop my essay from being a statement of my opinion. If you own or know of a website that has information on this topic it would be much appreciated.