An article by Jef Raskin, who was a leading thinker in user experience and user interface design. His book, The Humane Interface, had a profound impact on my views on human-computer interactions.

Excerpt from the article:
"One of the most common terms of praise for an interface is to say that it is "intuitive" (the word should have been "intuitable" but we will bow to convention). Yet the Human Computer Interaction (HCI) literature rarely mentions the word, and for good reason. This note attempts to clarify the meaning of "intuitive" for non-HCI specialists..."