This document categorizes and discusses deceptions in online social networks. It identifies common deceptions like phishing, account hijacking, identity cloning, Sybil attacks, spam, and diffusion of misinformation. It then outlines potential prevention and detection solutions, including using profile and network similarities to detect identity cloning, analyzing message content to detect spam, and algorithms like SybilGuard and CredRank to evaluate user trust and information credibility in order to limit the spread of deception. The document concludes that effective trust mechanisms are needed to prevent deceptions in online social networks.