2.1. History of Social Networks
Social networking sites allow its participants to connect with each other and build relations among people who have the same interests and activities (Das & Sahoo, 2011; Boyd & Ellison, 2007). Social networking is defined based on three perspectives: 1) build public and semi-public profiles, 2) articulate a list of friends who share a connection, 3) and view and traverse friends’ lists. These three characteristics make the social networking sites differ from previous media (Ahn, 2011; Boyd & Ellison, 2007). Social networks enable users to share and upload different types of photos, music, and videos that they like to share with others. In addition, this type of site provides a resource of information and a relation with other people, and emotional and social support (Dogruer, Menevis & Eyyam, 2011). Social media tools allow people to develop and maintain social relationships in ways that appear to differ in quality and quantity than face-to-face relationships (Hemsley & Mason, 2013, p. 141). The first social networking site Classmates.com was launched in 1995, the Purpose of its building was to give the students a connection during or after their degree completion (Ahmed & Qazi, 2011). Then, SixDegree.com was built in 1997 focusing on the idea that every user is tied with everybody else via six degrees of separation (Boyd, & Ellison, 2007; Das & Sahoo, 2011; Ahmed & Qazi, 2011), then a chain of social networking sites were built such as: Cyworld in 2001, Friendster in 2002, Skyblog in 2002, Orkut in 2004, Myspace in 2005, Yahoo 360 in 2005, Twitter in 2006 and Facebook in 2006 (Ahmed & Qazi, 2011). Nowadays, there are more than 100 social networking sites connecting millions of people.