Twitter is a free micro-blogging / social networking service that allows users to post "updates" or "tweets" (text-based messages up to 140 characters long) on their Twitter profile. Tweets can be posted directly on a user's profile, sent from third party applications like Twitterific or Twhirl, sent via SMS or IM, or posted via RSS. Once posted on a profile, tweets are sent to all users who have agreed to receive them. Users can receive tweets via their Twitter profile, SMS, email, IM, RSS or a third party application. Twitter members are able to express their individualism by customizing their Twitter templates, displaying a twitter personal image and twitter profile message. Twitter's social aspect is highlighted by an ability to add friends and have other Twitter members add you as a friend. The more friends (followers) you have, the more exposure your tweets receive. Twitter members can send direct messages to each other and engage in convers...