Abstract The early concept of the World Wide Web was the network of related (linked) documents represented in human readable form. The ongoing development leads to another aspect of the web, the web of data. The goal being that the network will provide first-class, machine readable data. Therefore the current network will be transformed to a network where the machines will not only serve as the platform that hosts human readable data but as a true machine–machine network. In this paper, we review and compare the formats, technologies and approaches that are used today for publishing semantic, machine readable data, on the web.