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There is a huge number of online communities and social networking sites, the most popular attract millions of users. Popular services include:

• Facebook – for everyone. Keep in touch with family and friends.
• Linkedin – for professionals. Keep in touch with colleagues past and present and network with people in your line of work or industry.
• Twitter – for everyone. Post updates to your followers. Limited to 140 characters per post.

Other types of communities

• Forums or message boards – people with similar interests post and reply to one another.
• Instant messaging – send instant messages to colleagues, friends and family.
• Blogs – short for web-log, usually about the owner of the blog or a specific subject.

Advantages of online communities and social networking

• Easy to keep in touch with friends and family wherever they are.
• Make new friends and find old ones you may have lost contact with.
• Share ideas, photos, music and video clips.
• Chat with friends for free.
• Play games alone or with friends.
• Funded by adverts so are free to use.

Disadvantages of online communities and social networking

• Users can hide behind false online identities, which can be dangerous.
• People you don’t know may gain access to your personal information.
• If you don’t apply security settings, a potential employer may see something you’ve posted online that they don’t like or agree with and decide not to hire you.
• Targeted adverts can be unsettling and intrusive.
• Viruses are becoming increasingly common on social networking sites.
• Keeping up to date and active in all of these communities can take up a lot of time.
• Meeting people online can be less fulfilling when compared to meeting people face to face.