Friday is Twitter's eighth birthday — and boy, has it come a long way. In that time, the social networking site has evolved into an invaluable resource for news (and it's not a bad place to find out what Katy Perry is up to). With more than 51 million followers, the pop star is — for now, at least — the reigning queen of Twitter.
So who's her competition? We compiled the top 10 most-followed Twitter accounts — five women, three men and two brands — to see how they compare.
See also: The Illustrated History of Twitter
Below, check out how the top accounts stack up: Who has tweeted the most? Who follows the most accounts? And, most importantly, who had the most embarrassing first tweet?

Image: Mashable Infographic.
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