Social networks play a significant role in information sharing and have become an essential part of user's daily activities. Social networks help share users' ideas, views, status and opinions in the form of text, music and videos. The inherent difficulties involved in sharing the information is the sustenance of the values attached to the dependability of the functional blocks of the user - identity, sharing, conversation, relationship, presence, group and reputation. Review of social networks in terms of user influence ranking would throw light on the role of these functional blocks. The user influence ranking generally reveals the impact that an individual has on the social network. In the present scenario, the user influence ranking factors are not systematically determined. Instead, each social network adopts its own method to determine users' influence. Hence, the review has been done to identify the adoption of these functional blocks in popular social networks to determine users' influence ranking method.