Before we can discuss Twitter or any of its competators, the basics of the technology must be understood. Once a blog has been published, each post can either be read on the original page, or, if the blogger is at all interested in getting people to read his or her page, the blog can be read in RSS format. An RSS (Really Simple Syndication) feed is a blog that has been digested into machine code so that it can be viewed with many other feeds in a standardized form. Feed readers like Google Reader or the reader built in to Flock make it easy to read a lot of different blogs, all at the same time.
If a post is too long, it either has to be truncated in RSS or it will take up a large portion of the feed. While regular weblogs struggle with this, sites like Twitter excel at making lots of short posts. Each Twitter user has an account from which they can post little blurbs up to
An example of what this kind of microblogging looks like is posted on the left side of this page. What you can see is a live feed of my Tweets that have been ported over from my Twitter account (Loyaleagle) and relayed as an RSS feed. I can post about what's going on in my life, send private messages to other users, and generally get a quick pulse of how my friends and favorite organizations are doing. That's right, a lot of companies and groups have Twitter feeds that they update with information about product updates and just crazy stuff happening in their part of the world.
There are a number of competitors, Jaiku and Pownce ranking near the top, but as with any social network, the one with the most of your friends is going to be your choice. I don't really have many friends on Twitter (it isn't very popular in the college scene yet), but I have found that most of the things I follow online are attached to a Twitter feed. Facebook has a similar feature with the "status" update you can apply to your profile, but because it is grounded in RSS, there are many more ways to display a Twitter feed.
Anyway, good luck Twittering and let me know what YOUR favorite microblogging agent is!
Edit: corrected the length of a twitter post
The image ("My Twitter Friends: update") was created by Flickr user "Josh Russel" and is licensed under a CC Attribution-Noncommercial-Share Alike 2.0 Generic License.
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