Many people, usually those who aren’t using Twitter yet, are under the impression the service has only just launched. In many respects it has, but at four years old it’s fair to say it has officially flown the start-up nest.

Four year ago today (we’re a few hours in in Europe), Twitter co-founder CEO Jack Dorsey tweeted the first Tweet ever. His words, while not as memorable as Neil Armstrong’s “One Small Step…”, are monumental all the same.

Picture 2 Happy Birthday Twitter. This little bird is all grown up...

The initial idea of Jack Dorsey that resulted in the development of Twitter is available on Flickr but before you shoot off to read of it, a couple of videos worth watching.

1) The Twitter Story: Twitter co-founder Biz Stone shares the Twitter story during the All-Alumni Reunion Conference at UC berkeley in April 2009.

The Second) Let Robert Scoble and CBS take you back to 2007 when the service was just beginning to make waves. This is back when Scoble was excited to have 2000 followers…