People need to explore information spaces:
to understand the content of the database
to extract the information of interest
to verify retrieved information matches expectation

Interaction Techniques:
Information Workspaces: fish eye = focus + context (multiple level of details)
Rainbow Search: Search on multiple data such as footnotes, headings, references, etc.
Search Expansion: System suggests general/specific terms (multiple abstraction)
Sonification: Search by sound
Pictorial Query-By-Example: Search by image similarity
Hyperbook: Search by multiple media, uses bird calls or bird sketches to retrieve bird families in an electronic book
The user can also retrieve a bird by drawing a silhouette of the bird