The Semantic Web
In contrast to the conventional Web, the “Web of documents”, the Semantic Web is the “Web of data” . The Semantic Web provides machine-processable data, making it possible for software agents to “understand” the meaning of information (i.e., semantics) presented by Web documents. This feature can be used for a variety of services , e.g., museums , community sites , or podcasting . The Semantic Web is a major aspect of Web 2.0 .
Linked Data can be applied to improve the exploitation the “Web of data”. The expression refers to the publishing of structured data in a way that they can be interlinked  to provide a higher level of usability. By using Linked Data, it is possible to find other, related data .
One of the most well-known images about the variety of datasets published in Linked Data is the LOD cloud diagram (Figure 1). Contributors include the Linking Open Data community project, individuals and organisations. It is based on metadata collected and curated by CKAN directory contributors .
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