Twitter is an online social networking service that enables users to send, or ‘tweet’, 140-character messages, or ‘tweets’.
Users must register to post tweets, though unregistered users can read tweets without having to sign up. Users can access the service via desktop, SMS or mobile device app.
Users can subscribe to other users’ tweets, known as ‘following’, with subscribers known as ‘followers’. Users can retweet other users’ tweets, or quote tweets and add a message of their own.
