Twitter introduced the retweet button in 2009. Before the button existed, users manually copied another person’s post and prefixed it with “RT @username” to show that they were forwarding the message.
This informal retweet convention began developing in 2007. It became especially important during the 2009 Iranian presidential election protests, when Twitter users circulated updates from observers and participants. The practice demonstrated the value of quickly redistributing posts beyond their original audience.
In August 2009, Twitter began integrating retweeting into the service. The company added retweet buttons to posts and replaced the manually typed “RT” format with an official retweet mechanism. This made sharing faster and preserved a clearer connection to the original author.
Retweeting later gained a related format called quote tweeting, which lets users add their own commentary. That is distinct from a standard retweet, which redistributes the post without adding a separate message. Twitter renamed itself X in 2023, and the retweet function is now commonly described as reposting.