Book excerpt: The Social Internet of Things (SIoT) has become a hot topic in academic research. It employs the theory of social networks into the different levels of the Internet of Things (IoTs) and has brought new possibilities for the development of IoTs. Essentially, the SIoT is a subset of IoTs. It uses intelligent hardware and humans as the node, a social network as the organization type, the social relationship between things, things and humans, and between humans, formatting research methods and models with social network characteristics to realize the connection, service, and application of the IoTs. Moreover, SIoT is a form of realization of technology, architecture, and application of the IoTs using social network research methods. It further promotes the integration between real-world and virtual cyberspace, contributes the realization of the IoTs, expands the research scope of the social networking, and provides a new solution for the specific problems of the IoTs. Consequently, there is a tremendous need for researchers to have a comprehensive knowledge of the advances in SIoT. This special issue is soliciting scientific research papers that can present a snapshot of the latest research status of SIoT.