Some people in the design community insist on calling website menu systems “information architecture.” I think they do it to make menu design sound sexier or more esoteric. Unfortunately that’s not what information architecture is. Or rather, it’s only part of what information architecture is.
Information architecture (IA) is actually “the structural design of shared information environments.” It’s no good just having a well-thought-through menu system for your site. Once you get people to where they need to be, the content needs to be arranged in the way they expect, using words they understand. Knowing how your users think about and self-categorize your site’s content should be central to your whole design effort. It boils down to finding out how your users think about and categorize the concepts, tasks, and activities that your product deals with, and then creating an architecture that matches this world view. My course Foundations of UX: Information Architecture steps through the discipline of IA, and the practical steps needed to apply it to your projects.