Information Architecture is about structuring information to make it
easy to find. When it's easy to find products on your website, people
will buy more. When it's easy to find information on your Intranet,
employees will save time and have the knowledge they need. Information
Architects are specialized in understanding problems that people face
when looking for information and designing ways to fix those problems.

http://iainstitute.org/en/learn/resources/elevator_pitches.php