Twitter
The first version of Twitter was only for Odeo employees to use. They opened the full version for anyone to use on July 15, 2006. In October 2006, Biz Stone, Evan Williams, Dorsey, and other members of Odeo started a new company called Obvious Corporation. Obvious Corporation bought Odeo and all of its property–including Odeo.com and Twitter.com–from the investors and shareholders. Twitter became its own separate company in April 2007.