It depends on the system... anywhere from 13 to 18.
For Facebook, Bebo, Hi5, PerfSpot, and Netlog, the minimum is 13.
For My Space, the min. is 14.
For Friendster and Zopria, is it 16.
For Orkut and Yahoo! 360 it is 18.
Mostly 18
The minimum will likely be 13 since that's the age you can give away your own personal data in the USA, where most of the companies operating these sites reside.
The age limit is usually 13 or 14.
Some online social networking sites that are considered to be safe for kids are Togetherville, ScuttlePad and Skid-e Kids. Because of the dangers of general social networking sites, these sites were created and strictly monitored to allow kids to interact safely.
Try to search what are the social networking sites and sign up in those sites.
social networking
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Social networking sites could be good and bad.
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Social networking sites. Do you know any proxies to get on these sites while at a computer with a ban on social networking?
Some social networking sites that College Candy is part of are Twitter, Facebook and Pinterest. Others social networking sites are Myspace and Google+.
scope of social networking sites
The name for people obsessed with social media networking sites is Internet addiction disorder.
According to various social networking sites Skandar is engaged to a one Stephanie Stiller from London.