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Drupal is an open source content management system (CMS) written in PHP. Known for being extremely flexible and extensible, Drupal is supported by a community of over 630,000 users and developers. Drupal sites can be customized and themed in a wide variety of ways.
Drupal functions as the “front-end” of Islandora.
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Fedora (Flexible Extensible Digital Object Repository Architecture) is an open source architecture for storing, managing, and accessing digital content in the form of digital objects. Fedora defines a set of abstractions for expressing digital objects, asserting relationships among digital objects, and linking "behaviors" (i.e., services) to digital objects.
The Fedora repository functions as the “back-end” of Islandora; files are stores as objects in the repository and accessed through the “front-end” (i.e., Drupal).
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Faceted searching allows users to filter a set of search results using predetermined classifications. For example, a user might search by title and then have the option to filter those results by selecting from a list of subjects and collections.
You can use Solr to configure your faceted search options.
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Any Fedora object is represented by a complete FOXML document. For more information, please see Managing access control with permissions and user roles (http://drupal.org/node/22275).
The namespace is a component of the persistent identifier (namespace:ID). The namespace is defined in the collection policy, and will then be used to generate PIDs for the objects ingested into that collection.
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Objects in a Fedora repository are organized using Resource Description Framework (RDF) statements.These statements define the relationships between objects in the following format:
<subjectFedoraObject> <relationshipProperty> <targetFedoraObject>
These RDF statements can define a number of relationships; for example:
<imageOfMap> <isMemberOf> <myMapCollection>
In this example, the map image belongs to the map collection.
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And XSD file - which stands for XML Schema Document - contains a set of rules to which an XML document must conform in order to be considered ‘valid’.
In the Form Builder context, the XSD file defines the schema that you are creating a form for. Schema's XSD files are usually hosted by the project's website, although you may upload a schema directly to your server.