Overview

Keywords are words or phrases that describe the metadata resource.  They facilitate search, discovery and indexing of metadata. They are also the largest single component of many metadata collections, regardless of the dialect. Using common types to classify these keywords is critical for consistent discovery, particularly using faceted searches. Shared vocabularies that include these new types are important contributor to consistent, interoperable metadata. The keyword types in italics are supported by NASA Global Change Master Directory (GCMD) and used in many existing metadata collections.

ECHO to ISO Keyword Mapping