This document provides an introduction to Twitter, explaining what Twitter is, how to set up an account, how to link your mobile device, the different components of your Twitter homepage, who to follow, how hashtags work, and how to use backchannel chat with hashtags. It describes Twitter as a social networking site where users post 140 character messages called "tweets" and follow other users. It outlines the steps to set up an account, link a mobile device to receive tweets by text, and customize account and device settings. It recommends following friends, family, and colleagues with shared interests and explains how hashtags allow users to search for and join topic-specific conversations.