The PBCore metadata standard (Public Broadcasting Metadata Dictionary) was created by the public broadcasting community in the United States of America for use by public broadcasters and related communities that manage audiovisual assets, including libraries, archives, independent producers, etc. PBCore is organized as a set of specified fields that can be used in database applications, and it can be used as a data model for media cataloging and asset management systems. As an XML schema, PBCore enables data exchange between media collections, systems and organizations. Background Initial development funding for PBCore was provided by the Corporation for Public Broadcasting starting in 2001. 1.0 – April 2005 PBCore Version 1.0 defined 48 metadata elements which combined to describe a media asset or resource's intellectual content, creation, creators, usage, permissions, constraints, use obligations, and its form or format in the physical or digital realm. 1.1 – January 2007 PBCore Version 1.1 enhanced the binding of related metadata elements (such as Title and TitleType) into new, hierarchically-organized "Element Containers." In that arrangement, each Element Container collects and houses associated "child" Elements that are thematically related. Basically, what was a "flat" arrangement of the 48 PBCore elements became a more "nested" structure of 53 elements, arranged in 15 containers and 3 sub-containers. 1.2.1 – December 2008 PBCore version 1.2.1 was published to better accommodate the possibility that a media asset may have multiple instantiations with various technical attributes. A new container called "pbcoreEssenceTrack" contains all other new elements to express different attributes associated with multiple instantiations. PBCore v1.2.1 used 61 elements organized into 15 containers and 4 sub-containers. 1.3 – August 2010 PBCore version 1.3 added a new top-level element, a new attribute of string values, and removed the previous requirement to describe one or more instantiations of any asset. Its new element, "pbcoreAssetType," could be used to explicitly declare the asset's broad business purpose, and its new attribute "source" could help clarify the text value of an element, much like the attribute "version" has done. PBCore v1.3 used 62 elements organized into 15 containers and 4 sub-containers. 2.0 - November 2011 PBCore version 2.0 was released at the annual conference of the Association of Moving Image Archivists in November 2011. This was a major revision of the schema, with the addition of two new top-level elements: The ""pbcoreCollection"" element allows for wrapping any number of pbcoreDescriptionDocuments in a collection or feed for exchanging