Read the text and answer the following questions.
1 What

Read the text and answer the following questions.
1 What is a social networking system?
2 How can you become part of one?
3 What are the benefits of being part of such a system?
4 How are such systems different?
5 What is the most popular system called? How did it develop?
6 What are the drawbacks of being a member of such a system?
Apparently quite a few other people have had the same idea, which accounts for the increasing popularity of social networking systems online networks of people linked together in much the same way documents are linked together on the web. In a typical scenario, I register on a web page and send invitations to my friends to become part of my network or community. My friends, in turn, invite their friends and so on. Only after joining the network (on the invitation of a trusted third party) can someone see my personal details e-mail address, location, hobbies, interests, and the like. Since everyone in the network is a quot;friend of a friendquot; (though perhaps several times removed , we all have a greater level of comfort about contacting each other and sharing information. Some of these networks are geared primarily toward dating, some are strictly for business contacts or employment searches, and still others are more general-purpose for making friends, finding people to join you in recreational activities, or discussing common interests.
Certain social networking systems are exclusive and invitation-only: you cant join unless you know someone whos already a member but once you do join, you can contact (and be contacted by) anyone in the network. Other services allow anyone to join, but restrict newcomers activities until theyve been approved or quot;sponsoredquot; by an existing member. Still others maintain multiple, non-overlapping networks, so that I can start my own network without an invitation, but I dont get access to members who are part of another network unless the two groups share at least one member in common. Usually you can search for people you know who are already part of a network, and once such a person verifies tha: youre a friend, you then have access to all your friends friends and their networks.
Social networking systems of one sort or another have been around for a number o* years, but they reached fad status only in 2003, thanks to the service known as Friendster. Withi-three months of its debut, Friendster had ove-a million members. A year later, the numbe-had passed seven million. Meanwhile, competing sites sprang up by the truckload, each with its own spin on the networking concept. These sites proliferated so quickly that they soon became known by the acronym YASNS (quot;yet another socia networking systemquot; . But while membership has steadily increased, actual use is another story. For example, while researching this article I searchec Friendster for people in my address book anc found quite a few but also found that most of them hadnt logged in for many months. In fact, all of the networks Ive investigated have a sizable percentage of quot;stalequot; members. Besides the time and effort required to use the systems, man. users have found that quot;friends of friendsquot; aren i necessarily people they want to have relationships with. For example, I noticed today that one of nr. friends had a friend with whom Ive had some unpleasant dealings in the past. My friend ma. trust him, but I dont yet hes now part of m. network. Still another difficulty is that most o* these networks are completely distinct from eacr other. If your friends do not all use the same system, it becomes very difficult to maintain a coherent network of contacts.