Over the last years, an increasing number of web sites have started to embed structured data into HTML documents as well as to publish structured data in addition to HTML documents directly on the Web. This trend has led to the extension of the Web with a global data space—the Web of Data. As the classic document Web, the Web of Data covers a wide variety of topics ranging from data describing people, organizations, and events over products and reviews to statistical data provided by governments as well as research data from various scientific disciplines. This chapter gives an overview of the topology of the Web of Data. We discuss the different techniques that are used to publish structured data on the Web and provide statistics about the amount and topics of the data currently published using each technique.