Social networking sites on the Internet can be categorized according to their main purpose, as follows:

• Contact sites
• Social Networking Sites
• Visual Information Sharing sites
• Game and Interactive Virtual Reality sites

Contact Sites

Sites such as Linkedin, PLAXO, or Friends Reunited, whose primary purpose is to share contact details and provide links permitting others to access the details of friends and contacts. They are used by both individuals and organizations to keep track of contacts and to widen their contact base through exploiting the links to „friends of friends?.

Social Networking Sites

These include sites such as Facebook, MySpace or even TWITTER whose primary purpose is to allow people to provide a „shop-window? on their life, and to share aspects of their life with others. Although in most cases these are primarily personal sites, other organizations are increasingly exploiting these sites for commercial purposes

Visual Information Sharing Sites

A number of sites such as You Tube or Flickr permit the sharing of video and still photo content. In addition to personal video clips, You Tube does carry product advertisements, instructions for the use of products, and film/TV trailers.

Game andInteractive Virtual Reality Sites

Virtual worlds or Metaverses are 3-dimensional virtual realities where an individual may create their own personal avatar and interact with others. There are many interactive worlds in the internet community where people may play games, notably fulfilling a desire to engage in wargames as an orc or an elf, though there are many different simulations available. These are referred to as massively multiplayer online role playing games (MMORPG).

Security and Privacy Issues

Social networking sites do carry a great deal of personal information, and the unwary or uninformed user may easily give away a great deal more information than they had intended.

Mobile phone technology provides easy and instant digital camera and video facilities, and this can be used maliciously. The filming of an assault and then posting the video on social networking sites is considered to enhance the image of the attacker.

Cases of cyber bullying, misuse and corruption of personal information, the posting of material about an individual by third parties, often of a malicious nature, and publishing of material involving others, without their consent, which can be embarrassing or worse.

Identity theft becomes easier if social networking sites can be mined to provide in-depth information on an individual. Search engines are emerging, which specifically focus on collating personal information from social networking sites

Within virtual reality sites, various further issues arise. In part these are to do with the psychology of the sites themselves. People will have a strong bond with their avatar, whether it is the child whose penguin has the bright red scarf or the adult whose alter ego is everything he is not.

Another major issue is the extent to which virtual reality sites allow an individual to screen their real identity. Whilst it allows you to hide behind a virtual identity, it also allows others to do the same, and this may be exploited. Confidence tricksters and other criminal individuals also prey on trusting adults

Real-life crime will inevitably intrude into virtual reality sites if they can. Second Life, for example, allows cash transactions using virtual Linden Dollars, which are negotiable currency and can be bought and sold in real life. Virtual goods can be bought and sold, and therefore theft, fraud, money-laundering etc. become possible

What Can Be Done?

For the individual, the most effective solution remains education of the user to keep him/heralert to what may happen and the precautions which can be taken. We need to make people aware that the Internet is not, in reality, a private place. The citizens should be guided of the advantages and of the risks of social networking sites, and provided an overall awareness, particularly to the young and vulnerable,  about the need to be cautious in what they do online.

From a corporate perspective, a revised security model which takes into account the sharing of information across social networks is necessary. There are risks in the use of and social networking software, though these are often not well recognized

A strengthening of legislation designed to protect personal information is necessary, and also work to define and then to protect data ownership rights in a web-based environment.