ABSTRACT
The emergence of smartphones with rich applications and with the ability of positioning such devices in real-time has made location-based social networks (LBSNs) increasingly popular. In this chapter, we discuss the basics of LBSNs with specific examples of commercial LBSN services offering different scopes and objectives. We also discuss how the data from LBSNs are being employed by the research community for understanding and addressing a variety of problems.
