基本的语义web堆栈已经在这篇文章中解释了很多。我想把重点放在最初的问题上，并比较RDF和OWL。

OWL是RDF和RDF- s的超级集(在上面) OWL允许有效地使用RDF和RDF- s OWL有一些扩展的词汇表 类和个人(“实例”) 属性和数据类型(“谓词”) OWL是正确的推理和推断所必需的 OWL有三种方言，精简，描述逻辑和完整

使用OWL是通过了解一些事实来获得更多意义(推理和推断)的必要条件。这种“动态创建”的信息可以进一步用于像SPARQL中那样的一致查询。

一些例子将显示这实际上与OWL一起工作——这些都是从我2015年在西班牙马略卡的TYPO3camp上关于语义网基础知识的演讲中摘录出来的。

规则等价

Spaniard: Person and (inhabitantOf some SpanishCity)

这意味着西班牙人必须是一个人(因此继承了推理部分中的所有财产)，并且必须至少居住在一个(或多个)西班牙城市。

属性的含义

<Palma isPartOf Mallorca>
<Mallorca contains Palma>

该示例显示了对属性isPartOf和contains应用inverseOf的结果。

逆 对称的 传递 不相交的 .．.

属性的基数

<:hasParent owl:cardinality “2“^^xsd:integer>

这定义了每个事物(在这个场景中很可能是人)都有两个父元素——基数被分配给hasParent属性。

最低 最大 确切的

RDF是一种定义三元“主语”、“谓语”、“值”的方法。 例如，如果我想说，

"我叫皮埃尔"

我会写

<mail:me@where.com> <foaf:name> "Pierre"

参见<foaf:name> ?它是FOAF本体的一部分。本体是描述给定主题的属性和类的正式方式，OWL是定义本体的一种(RDF)方式。

你使用c++， Java等等…定义一个类，一个子类，一个字段，等等…

class Person
{
    String email_as_id;
    String name;
}

RDF使用OWL来定义这类语句。

另一个问这类问题的地方:http://www.semanticoverflow.com/

我试图掌握语义网的概念。我发现这很难 来理解RDF和OWL之间的确切区别。是 OWL是RDF的扩展或者这两者是完全不同的 技术吗?

简而言之，是的，您可以说OWL是RDF的扩展。

In more detail, with RDF you can describe a directed graph by defining subject-predicate-object triples. The subject and the object are the nodes, the predicate is the edge, or by other words, the predicate describes the relation between the subject and the object. For example :Tolkien :wrote :LordOfTheRings or :LordOfTheRings :author :Tolkien, etc... Linked data systems use these triples to describe knowledge graphs, and they provide ways to store them, query them. Now these are huge systems, but you can use RDF by smaller projects. Every application has a domain specific language (or by DDD terms ubiquitous language). You can describe that language in your ontology/vocabulary, so you can describe the domain model of your application with a graph, which you can visualize show it to business ppl, talk about business decisions based on the model, and build the application on top of that. You can bind the vocab of your application to the data it returns and to a vocabulary known by the search engines, like microdata (for example you can use HTML with RDFA to do this), and so search engines can find your applications easily, because the knowledge about what it does will be machine processable. This is how semantic web works. (At least this is how I imagine it.)

Now to describe object oriented applications you need types, classes, properties, instances, etc... With RDF you can describe only objects. RDFS (RDF schema) helps you to describe classes, inheritance (based on objects ofc.), but it is too broad. To define constraints (for example one kid per chinese family) you need another vocab. OWL (web ontology language) does this job. OWL is an ontology which you can use to describe web applications. It integrates the XSD simpleTypes. So RDF -> RDFS -> OWL -> MyWebApp is the order to describe your web application in a more and more specific way.

在WC3文档对象模型中，文档是一个抽象的东西:包含文本、注释、属性和其他嵌套元素的元素。

在语义网中，我们处理的是一组“三元组”。每个三重是:

一个主题，三元组的内容，id，数据库主键，一个URI;而且 谓词，“动词”，“属性”，“数据库列”-另一个URI;而且 对象，原子值或一些URI。

OWL之于语义web就像schema之于W3C文档对象模型。它记录了各种uri的含义，并指定如何以一种可以由机器检查的正式方式使用它们。语义web对于应用于它的OWL可能有效也可能无效，就像文档对于模式可能有效也可能无效一样。

RDF之于语义网就像XML之于DOM——它是一组三元组的序列化。

当然，RDF通常被序列化为XML文档……但重要的是要理解RDF与“RDF的XML序列化”不是一回事。

类似地，OWL可以使用OWL/XML序列化，或者(不好意思)可以表示为RDF，而RDF本身通常序列化为XML。

The Resource Description Framework (RDF) is a powerful formal knowledge representation language and a fundamental standard of the Semantic Web. It has its own vocabulary that defines core concepts and relations (e.g., rdf:type corresponds to the isA relationship), and a data model that enables machine-interpretable statements in the form of subject-predicate-object (resource-property-value) triples, called RDF triples, such as picture-depicts-book. The extension of the RDF vocabulary with concepts required to create controlled vocabularies and basic ontologies is called RDF Schema or RDF Vocabulary Description Language (RDFS). RDFS makes it possible to write statements about classes and resources, and express taxonomical structures, such as via superclass-subclass relationships.

Complex knowledge domains require more capabilities than what is available in RDFS, which led to the introduction of OWL. OWL supports relationships between classes (union, intersection, disjointness, equivalence), property cardinality constraints (minimum, maximum, exact number, e.g., every person has exactly one father), rich typing of properties, characteristics of properties and special properties (transitive, symmetric, functional, inverse functional, e.g., A ex:hasAncestor B and B ex:hasAncestor C implies that A ex:hasAncestor C), specifying that a given property is a unique key for instances of a particular class, and domain and range restrictions for properties.

一图胜千言!下面这张图应该可以加强克里斯托弗·古特里奇的观点 在这个回答中说语义网是一个“分层架构”。

来源:https://www.obitko.com/tutorials/ontologies-semantic-web/semantic-web-architecture.html