In the beginning introduction, the social networking sites (SNSs), like MySpace, Facebook, Cyworld, and Bebo have attracted millions of users. Even SNSs have applied and become part of everyday life prektek human. SNSs also supports their interests. SNSs Originally created to preserve the relationship between individuals which has been stranded. Some sites also aims at linking between individuals who do not know each other, but have similar views and interests, as in political terms. There SNSs that serve audiences with different characteristics, some are serving an audience of common identity, such as language, racial, sexual, religious, or nationality.
Currently SNSs vary in ability as a means of communication and exchange the latest information, such as mobile connectivity, blogging, and photo / video sharing. The experts from various fields of many researching SNSs to understand practice, implications, and the culture of SNSs itself.

Definition of Social Networking Sites
We define social network sites as web-based service that allows individuals to: build relationships with other people who restricted a system, knowing the other user’s network, and expand connections through other users.
Unique social networking sites and popular not because it allows individuals to meet and establish communication with strangers, but because of its ability to open the social network for everyone. In some big SNSs, users do not need to look for people to expand the network, but they can directly communicate with people who have become part of an extensive network.
SNSs vary greatly in terms of features. Some SNSs already have the ability to instant message and share photos or video. We have SNSs dedicated to mobile, but also web-based SNSs supports access through mobile phones, such as Facebook, MySpace, and Cyworld.
After joining an SNS, an individual will be asked to fill out a form that contains a series of questions to view the profile. The question usually includes a description, such as age, location, interests, “about me”, etc.. Most sites also allow users to upload a profile picture and modify the profiles by adding multimedia content. Visibility profiles between various SNSs also varies by site and user considerations. Even today there SNSs for dogs (Dogster) and cats (Catster), whose profile is governed by the owner of the animal.

History of Social Networking Sites
AIM and ICQ buddy lists supported lists People, even people that’s not visible to others. Classmates.com allow people to join the school or college and surf the network for others who are also related, but users can not create a profile or list Friends until years later. SixDegrees was the first to incorporate these features. SixDegrees promoted itself as a tool to help people connect with and send messages to other people. While interested SixDegrees millions of users, it failed to become a sustainable business and, in 2000, the service closed.
Social networking site first became known and was launched in 1997. Beginning with the emergence SixDegrees.com that allows users to create profiles, friends list, and developed in 1998 with the ability to browse a list of friends.
Followed by the emergence of AIM and ICQ buddy who has a feature list of friends but can not be seen by other users. Next comes Classmate.com that facilitate people to join the school or college and explore the network with other users in the school. However, users can not create a profile or list of friends until a year later. Following a Live Journal which was created in 1999. In the end SixDegrees incorporate those features and be the first site that combines features of several SNSs at the time. However, SixDegrees failed to attract audiences and finally closed in 2000. Failure SixDegrees attract audiences associated with user complaints due to feature a bit so not much can be done after you approve a friend. In addition, most users when it is not so interested in meeting with a stranger. Subsequently in 2001, technological developments began to support various combinations of profiles.
Cyworld started in 1999 and adding SNS features in 2001. Later web community LunarStorm Sweden introduced himself as the SNS in 2000, contains a feature list of friends, guestbooks, and diary pages. The next wave began when SNSs Ryze.com was launched in 2001 to help people establish and utilize their business network. Ryze.com first introduced to the San Francisco business and technology community, including businessmen and investors SNSs.
In particular, the people behind Ryze, Tribe.net, LinkedIn, and Friendster, and other SNSs interwoven personally and professionally. They believe that they can support each other without competing (Festa, 2003).

Privacy
Current issues related to developing social networking sites are a threat to user privacy SNSs. Researchers have investigated the potential threats to privacy associated with SNSs. In one academic study on privacy and SNSs, Gross and Acquisti (2005) analyze and describe the potential threats to privacy through Facebook profiles containing personal information. As the possibility to reconstruct personal identity, such as hometown and date of birth. Barnes (2006) describe the “privacy paradox” that occurs when teens do not realize the public nature of the Internet.
However, survey data show that teens realize the potential privacy threats in SNSs and many are proactively taking steps to minimize risk. Pew found that 55% of teens who have profiles SNSs, 66% of them to set their profiles to not be visible to all Internet users (Lenhart & Madden, 2007). And the teenager who opened their profile for all Internet users, 46% of them are false personal information.
SNSs also challenged the legal concepts of privacy. Hodge (2006) argues that the fourth amendment to the U.S. Constitution and legal decisions about privacy are not equipped with privacy regulations in the social networking site.