Linked Data

✍ Scribed by Tom Heath, Christian Bizer

• Publisher: Morgan & Claypool Publishers
• Year: 2011
• Tongue: English
• Leaves: 137
• Series: Synthesis Lectures on Web Engineering
• Edition: 1
• Category: Library

✦ Synopsis

The World Wide Web has enabled the creation of a global information space comprising linked documents. As the Web becomes ever more enmeshed with our daily lives, there is a growing desire for direct access to raw data not currently available on the Web or bound up in hypertext documents. Linked Data provides a publishing paradigm in which not only documents, but also data, can be a first class citizen of the Web, thereby enabling the extension of the Web with a global data space based on open standards - the Web of Data. In this Synthesis lecture we provide readers with a detailed technical introduction to Linked Data. We begin by outlining the basic principles of Linked Data, including coverage of relevant aspects of Web architecture. The remainder of the text is based around two main themes - the publication and consumption of Linked Data. Drawing on a practical Linked Data scenario, we provide guidance and best practices on: architectural approaches to publishing Linked Data; choosing URIs and vocabularies to identify and describe resources; deciding what data to return in a description of a resource on the Web; methods and frameworks for automated linking of data sets; and testing and debugging approaches for Linked Data deployments. We give an overview of existing Linked Data applications and then examine the architectures that are used to consume Linked Data from the Web, alongside existing tools and frameworks that enable these. Readers can expect to gain a rich technical understanding of Linked Data fundamentals, as the basis for application development, research or further study. Table of Contents: List of Figures / Introduction / Principles of Linked Data / The Web of Data / Linked Data Design Considerations / Recipes for Publishing Linked Data / Consuming Linked Data / Summary and Outlook

✦ Table of Contents

List of Figures......Page 12
Preface......Page 14
The Data Deluge......Page 16
Structure Enables Sophisticated Processing......Page 17
Hyperlinks Connect Distributed Data......Page 18
From Data Islands to a Global Data Space......Page 19
Introducing Big Lynx Productions......Page 20
The Principles in a Nutshell......Page 22
Naming Things with URIs......Page 24
Making URIs Defererenceable......Page 25
303 URIs......Page 26
Hash URIs......Page 28
Hash versus 303......Page 29
The RDF Data Model......Page 30
RDF Serialization Formats......Page 33
Including Links to other Things......Page 35
Relationship Links......Page 36
Identity Links......Page 37
Vocabulary Links......Page 39
Conclusions......Page 40
The Web of Data......Page 44
Topology of the Web of Data......Page 45
Cross-Domain Data......Page 48
Media Data......Page 49
Government Data......Page 50
Libraries and Education......Page 51
Life Sciences Data......Page 52
User Generated Content and Social Media......Page 53
Conclusions......Page 54
Minting HTTP URIs......Page 56
Guidelines for Creating Cool URIs......Page 57
Example URIs......Page 58
Describing Things with RDF......Page 59
Literal Triples and Outgoing Links......Page 60
Triples that Describe Related Resources......Page 61
Triples that Describe the Description......Page 62
Describing a Data Set......Page 63
Licenses, Waivers and Norms for Data......Page 67
SKOS, RDFS and OWL......Page 71
RDFS Basics......Page 72
A Little OWL......Page 75
Reusing Existing Terms......Page 76
Selecting Vocabularies......Page 77
Defining Terms......Page 78
Making Links with External Data Sources......Page 79
Auto-generating RDF Links......Page 81
Patterns in a Nutshell......Page 84
Additional Considerations......Page 86
Serving Linked Data as Static RDF/XML Files......Page 87
Serving Linked Data as RDF Embedded in HTML Files......Page 89
Serving Linked Data from Relational Databases......Page 92
Serving Linked Data by Wrapping Existing Application or Web APIs......Page 94
Testing and Debugging Linked Data......Page 95
Linked Data Publishing Checklist......Page 97
Deployed Linked Data Applications......Page 100
Generic Applications......Page 101
Domain-specific Applications......Page 105
Developing a Linked Data Mashup......Page 108
Accessing Linked Data URIs......Page 109
Representing Data Locally using Named Graphs......Page 110
Querying Local Data with SPARQL......Page 111
Architecture of Linked Data Applications......Page 112
Accessing the Web of Data......Page 115
Vocabulary Mapping......Page 116
Identity Resolution......Page 117
Data Quality Assessment......Page 118
Effort Distribution between Publishers, Consumers and Third Parties......Page 120
Summary and Outlook......Page 124
Bibliography......Page 126
Authors' Biographies......Page 136