5 years ago, on July 15th, 2006, Twitter, then called Twittr, opened to the public. Twittr was described as “a new mobile service that helps groups of friends bounce random thoughts around with SMS.” The microblogging platform has grown into something founders Biz Stone, Jack Dorsey and Evan Williams could never have imagined.

At the start of this year, Twitter users in Japan set the tweets per second record at 6,939 tweets per second, 4 seconds after midnight in Japan on New Year’s Day. In March, Twitter users were sending 1 billion tweets per week. Today, to celebrate its 5th birthday, Twitter is tweeting out a few fantastic statistics, including this one:

Screen shot 2011 07 15 at 11.30.32 AM 520x207 5 years ago today Twitter launched to the public

The tipping point for Twitter’s popularity was the 2007 South by Southwest (SXSW) festival. During the event, Twitter usage increased from 20,000 tweets per day to 60,000. Since then, Twitter hasn’t been growing exponentially, it’s taken off like a rocketship. While it took Twitter more than 16 months to reach the first 600,000 Twitter accounts. Yesterday, Twitter saw the same number – more than 600,000 signups in just one day.

Could it be because Twitter is getting more proactive about signing up logged out users? Read about that here.

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