Twitter is a “microblogging” Web site. Recall that blogs emerged in the late 1990s and resembled online diaries. People could write anything they wanted and post it for people to read or comment on. While blogs could take any form, the posts were often essay length. Microblogging allows users to make posts, but they tend to be very short. Twitter limits posts to 140 characters. This creates an environment that is fundamentally different from blogging, since it is easy for someone to read hundreds of posts in a short amount of time. This chapter presents an overview of the different types of information people share on the site and how to find those people.