RDF Rules

RDF uses Web identifiers (URIs) to identify resources.

RDF describes resources with properties and property values.

RDF Resource, Property, and Property Value

RDF identifies things using Web identifiers (URIs), and describes resources with properties and property values.

Explanation of Resource, Property, and Property value:

• A Resource is anything that can have a URI, such as "http://www.w3schools.com/RDF"
• A Property is a Resource that has a name, such as "author" or "homepage"
• A Property value is the value of a Property, such as "Jan Egil Refsnes" or "http://www.w3schools.com" (note that a property value can be another resource)

The following RDF document could describe the resource "http://www.w3schools.com/RDF":

<?xml version="1.0"?>

<RDF>
  <Description about="http://www.w3schools.com/RDF">
    <author>Jan Egil Refsnes</author>
    <homepage>http://www.w3schools.com</homepage>
  </Description>
</RDF>

The example above is simplified. Namespaces are omitted.

RDF Statements

The combination of a Resource, a Property, and a Property value forms a Statement (known as the subject, predicate and object of a Statement).

Let's look at some example statements to get a better understanding:

Statement: "The author of http://www.w3schools.com/RDF is Jan Egil Refsnes".

• The subject of the statement above is: http://www.w3schools.com/RDF
• The predicate is: author
• The object is: Jan Egil Refsnes

Statement: "The homepage of http://www.w3schools.com/RDF is http://www.w3schools.com".

• The subject of the statement above is: http://www.w3schools.com/RDF
• The predicate is: homepage
• The object is: http://www.w3schools.com

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