Social Enterprise

Gallery: Five years after the first Twitter tweet

Hard to believe but on March 31, 2011 Twitter celebrated the fifth anniversary of its first tweet ,on twttr at the time, by co-founder Jack Dorsey.

As of today, the average number of tweets has reached 140 million per day - that's about 1 billion per week - with a high of 177 million on March 11 after the Japanese earthquake disaster.

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