Information architecture is the design and organisation of content, pages and data into a structure that aids users understanding of a system. A more organised system enables users to more easily find the information they require and complete the intended tasks.
To create an effective information architecture you need to understand the relationship between the content and the interoperability of the system you are designing. A flow or hierarchy is often established with IA that allows users to understand where they are, and where they can go next.
Information Architecture is a discipline of it’s own and can be performed by specialists or any other members of a design team. An Information architects output can be expressed visually through: site maps, wireframes, navigation, taxonomic designs, metadata and more.