UX Design, Interactive Design, Front-end Design, etc. are merely sub-sets (examples) of Information Architecture. IA is the science behind Collecting, Structuring, Presenting, and Comprehending information. Period. No where in that definition should you see website, application, software, etc.. If you do, then it's incorrect (wiki is wrong). Web pages and applications are merely two of the many tools used in presenting information.
- Organizing notes in a notepad (IA).
- Creating an outline prior to writing an essay (IA).
- Formatting comments in code (IA).
- Cataloging books in a library (IA).
- Creating a PowerPoint Presentation (IA).
- Cognitive Phycology [Human Computer Interaction] (IA).
I'm using Information Architecture right now to logically structure my information in a way that makes it easy for readers to follow and comprehend. I'm using this site as a tool to present my information. Now bear in mind that this may not be structured in the best way possible, which is why IA is a continuing science and not a standard.
NOTE: This Exchange (UX-User Experience) should have been named Information Architecture. UX falls under IA - IA does not fall under UX.