What is faceted search poor full-text search?

I even find out about it from Wikipedia, however i could not understand fully the utilizationOradvantage from it. Hope the city can answer/expand and explain with a few good good examples.

NOTE: We are into the entire process of evaluating/researching different open search full-text internet search engine and mostly I am seeing faceted search listed among the feature amongst others. So I am attempting to assess whether this is useful for the application requirement.

Faceted search is well-described here with an example.

EXAMPLE: Faceted Search

Faceted (or navigational) search utilizes a hierarchy structure (taxonomy) make it possible for customers to browse information by selecting from the pre-determined group of groups. This enables a person to key in their simple query, then refine their search options by moving/drilling lower. The truth is, this is an advanced search happening without anyone's knowledge, but rather than the consumer needing to think about the extra search groups, it has been made simpler on their behalf through the visible folder structure. Good examples of the are eCommerce sites like Amazon . com and eBay.