Embedded RDF

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Embedded RDF (eRDF) is a syntax for writing HTML in such a way that the information in the HTML document can be extracted (with an eRDF parser or XSLT style sheet) into Resource Description Framework (RDF). This can be of great use for searching within data.

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It was invented by Ian Davis in 2005, and partly inspired by microformats, [1] a simplified approach to semantically annotate data in websites. This specification is obsolete, superseded by RDFa, Microdata, and JSON-LD.

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The Resource Description Framework (RDF) is a family of World Wide Web Consortium (W3C) specifications originally designed as a metadata data model. It has come to be used as a general method for conceptual description or modeling of information that is implemented in web resources, using a variety of syntax notations and data serialization formats. It is also used in knowledge management applications.

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RDFa is a W3C Recommendation that adds a set of attribute-level extensions to HTML, XHTML and various XML-based document types for embedding rich metadata within Web documents. The RDF data-model mapping enables its use for embedding RDF subject-predicate-object expressions within XHTML documents. It also enables the extraction of RDF model triples by compliant user agents.

Semantic publishing on the Web, or semantic web publishing, refers to publishing information on the web as documents accompanied by semantic markup. Semantic publication provides a way for computers to understand the structure and even the meaning of the published information, making information search and data integration more efficient.

Semantically-Interlinked Online Communities schema for describing posts and interactions on forums, message boards, blogs etc.

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Geo is a microformat used for marking up WGS84 geographical coordinates (latitude;longitude) in (X)HTML. Although termed a "draft" specification, this is a formality, and the format is stable and in widespread use; not least as a sub-set of the published hCalendar and hCard microformat specifications, neither of which is still a draft.

Semantic HTML is the use of HTML markup to reinforce the semantics, or meaning, of the information in webpages and web applications rather than merely to define its presentation or look. Semantic HTML is processed by traditional web browsers as well as by many other user agents. CSS is used to suggest its presentation to human users.

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Semantic Web Stack The Semantic Web Stack illustrates the architecture of the Semantic Web.

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Named graph database model

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ShEx technical standard

Shape Expressions (ShEx) is a language for validating and describing RDF.

Linked Data Notifications (LDN) is a W3C Recommendation that describes a communications protocol based on HTTP, URI, and RDF on how servers (receivers) can receive messages pushed to them by applications (senders), as well as how other applications (consumers) may retrieve those messages. Any web resource can advertise a receiving endpoint (inbox) for notification messages. Messages are expressed in RDF, and can contain arbitrary data.

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