Twitter celebrates it’s fifth birthday today. Jack Dorsey’s first-ever tweet was sent on March 21, 2006, back when the site was known as Twttr.

Five years is quite a milestone for the platform, which now sees almost half a million new accounts registered each and every day, a billion tweets a week, and boasts 400 employees.

Yesterday, Dorsey reminisced about those pre-Twitter days.

Roll on birthday number six.