Bootstrap, originally named Twitter Blueprint, was developed by Mark Otto and Jacob Thornton at Twitter as a framework to encourage consistency across internal tools. Before Bootstrap, various libraries were used for interface development, which led to inconsistencies and a high maintenance burden. According to Twitter developer Mark Otto:
After a few months of development by a small group, many developers at Twitter began to contribute to the project as a part of Hack Week, a hackathon-style week for the Twitter's development team. It was renamed from Twitter Blueprint to Bootstrap, and released as an open source project on August 19, 2011.[4] It has continued to be maintained by Mark Otto, Jacob Thornton, and a small group of core developers, as well as a large community of contributors.[5]
On January 31, 2012, Bootstrap 2 was announced. This release added the twelve-column grid layout and responsive design components, as well as changes to many of the existing components.[6] The Bootstrap 3 release was announced on 19 August, 2013, moving to a mobile first approach and using a flat design.[7]
