Twitter was founded by Evan Williams, Jack Dorsey, and Biz Stone.
At the age of 22, Jack Dorsey had an idea of creating a program wherein he could use his RIM 850 cellphone to send text messages to a service wherein the message will then be sent to all his friends.
Problem was, his friends who didn't have phones like Jack where still using computers. He worked for a few year in order to try to solved this problem, and finally approached a podcasting company called Odeo which was also interested in the field of text messaging.
Before Twitter was conceived, Co-founder Evan Williams created Blogger, which is more popularly known today as Blogspot before Google purchased it on 2003. After this purchase, Williams started to work for Google. After a short while, Williams along with Biz Stone left Google and started the
company, that Jack would be joining, called Odeo.