ABSTRACT
Online social network (OSN) serves as a means of social activity and has become a mainstream information media in the industry and in the public. Social network services (SNSs) have gained their popularity and serve more and more granular target markets, such as medication, science, and education. The chapter reviews mainly technology factors, as well as their psychological and social backgrounds. It deals with a background of taxonomy of OSNs by comparing similar counterparts. The chapter proposes a taxonomy and retrospectively compares it with other online communities, and even pre-internet social networking communities. It attempts to plot the possible evolution directions and future technology challenges. OSNs are used extensively as public social interactive and collaboration tools. OSNs provide various applications to facilitate social interactions and impress other people by social presence. The counteraction of profile fragmentation is studied in L. Backstrom and his team, and K. Liu and E. Terzi, as a technical challenge.
