Difference between revisions of "Semantics"
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* Based on the obsolete idea that all of language can be divided into [[Syntax]] (order) and [[Semantics]] (meaning). | * Based on the obsolete idea that all of language can be divided into [[Syntax]] (order) and [[Semantics]] (meaning). | ||
| − | * Some data elements have meaning that is independent of the places where they are used. These cases are handled well with a [[Data Dictionary]]. | + | * Some data elements have meaning that is independent of the places where they are used. These cases are handled well with a [[Data Dictionary]]. See that wiki page for non-context-dependant semantics. |
* For data elements that are context-dependent, the meaning cannot be known without reference to the context. These cases need a richer model. | * For data elements that are context-dependent, the meaning cannot be known without reference to the context. These cases need a richer model. | ||
Revision as of 10:09, 24 April 2022
Full Title or Meme
When an Entity can determine the "significance" of words in sentences.[1]
Context
- Based on the obsolete idea that all of language can be divided into Syntax (order) and Semantics (meaning).
- Some data elements have meaning that is independent of the places where they are used. These cases are handled well with a Data Dictionary. See that wiki page for non-context-dependant semantics.
- For data elements that are context-dependent, the meaning cannot be known without reference to the context. These cases need a richer model.
Semantic Models
- Semantics in data processing goes back to the 1980's when EDI and XML structures were being defined.
- In the case of EDI all semantics were context-dependent. The concept context definition was introduced by Tom Jones at a meeting at MIT where a data type was defined to say that the following data values had meaning only in that document at that location.
- In the case of XML, the contexts were established at the top of the document and the specific context tag was prepended to the element name. So if the context name was "x", an element of that context would appear as x:tag.
- Data dictionaries appeared in the databases with the EAR or Entity Attribute Relational models used with languages like SQL.
- The Semantic Web can be dated to a paper by Tim Berners-Lee's paper[2] in 2001 and the publication of the OWL language in 2004.[3]
References
- ↑ Webster's Third International Dictionary, Etymology of Semantics
- ↑ Berners-Lee +2, The Semantic Web Scientific American (2001-05-17) https://www.scientificamerican.com/article/the-semantic-web/
- ↑ W3C, OWL Web Ontology Language Overview (2004-02-10) http://www.w3.org/TR/owl-features/
