Twitter is a tool for "micro-blogging" or posting very short updates, comments or thoughts. Twitter is becoming an increasingly important platform for online communication. Twitter marketing is all forms of Twitter uses for marketing purposes. It encompasses free and paid uses of Twitter’s services and applications by a brand but also all encouragements and incentives adressed to consumers to relay and amplify brand contents, messages and campaigns. Usually, customers relay brand messages and contents by using Twitter buttons and hashtags.