Facebook claimed 995m active users, as of June 2012. Twitter has about 500m users, and YouTube, owned by Google, says it has 800m visitors each month, watching 4bn hours of video. Renren, a Chinese social media site, claims 157m active accounts.
For marketing purposes alone, social media sites – designed for consumers to stay in touch with friends, publish photographs or share information about hobbies and interests – are an attractive platform.
And they are also economical: a standard Facebook page is free, even to the largest businesses.
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