Twitter is a web-based application interface that allows users to feed the data stream with their own generated input. Because the Twitter data stream is so large now (75 million accounts by end of 2009), there are plenty of useful ways to navigate that data.

Clearly the Twitter interface can be used to add your own input for any of the following reasons:

• To simply participate in the new phenomenon of tweeting
• To communicate with your followers or group
• To communicate with the World-at-large
• To archive your online and/or offline activities
• For branding a product or service
• Because it’s required by a school assignment

There are many tools for adding your own content either directly via Twitter.com’s interface, or by using any host of apps that enable multiple posting inputs such as Tweetdeck.com or Posterous.com that allow for a single post to enter the Twitter stream as well as update your Facebook or Linkedin status, your blog, your photo sharing app, etc. SocialOomph.com, Tweetlater.com, others like them, offer the ability to time-delay tweet postings as well as automate replies to new followers, etc. Apps like Grouptweet.com and Present.ly enable the formation of private groups for both input and output benefits.

These multiple input apps are attempting to simplify the needs of active Internet users. Is it a sustainable model? Time will tell but for now, it’s necessary as the crowd filters out the superfluous and drills down to the preferred mechanisms for communication.

However, an important alternative to merely adding to the data stream (input) is the myriad of ways people are using Twitter to monitor the output. There are many ways to listen to the data Twitter is streaming. Reasons to listen include: » More: Brief Summary of Twitter Uses