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A named role, such as "writer", that is assigned to a user, group or some other identifying principal within part of the repository. Roles may be used by the policy enforcement point (PEP) to authorize actions taken in the repository.
Checksum
An algorithmically produced A computed fingerprint for binary content, used to ensure a complete transfer or the fixity of stored information. Fedora supports the SHA1 SHA-1 checksum algorithm for safely uploading content.
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Properties are typed values that belong to Nodes. Properties can be restricted to a single value or can be a collection of values with the same name (A property's multiplicity is limited by the Node definition in which it is defined). They can be any one of the following types STRING, BINARY, LONG, DOUBLE, DATE, BOOLEAN, NAME, PATH, REFERENCE, WEAKREFERENCE, URI, and DECIMAL.
rdf:type
Is an An RDF property that is used to define that the Node described belongs to a class of functionality / behavior. For example http://www.w3.org/ns/ldp#Container is an rdf:type that denotes the node can contain other nodes. The official definition can be found here.
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A repository is a single, self-contained persistent store of information plus the software that is used to access and update that information. Fedora is a repository.
Transactions
A Transaction transaction represents a series of changes to the repository that must execute successfully and completely or not at all. They Transactions are used to ensure consistency. Each transaction must succeed or fail as a complete unit; it cannot remain in an intermediate state.
Uniform resource identifier (URI)
Is a A string of characters used to identify a name of a web resource. It is defined in section 3 of http://tools.ietf.org/html/rfc3986#section-3. An example of a URI would be "http://purl.org/dc/elements/1.1/".
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