Spring 2006 DLF Forum: Melvyl Recommender Project, 11
3 April, 2006
Faceted Browse
The idea of faceted browse is to allow the user to continually narrow the focus along several defined axes, each of which is a hierarchy.  An item is defined by several facets...e.g. location, material, time period....and they can be browsed as a whole, not separately.

As the user drills down, the display keeps track of what terms have been chosen, and offers further refinement into each facet.  The chosen terms can be removed in any order, so navigation within the faceted hierarchy is fluid.

There are numerous examples of full or partial implementation of this out in the world...Endeca supports it.