I have found that every explanation of twitter is the same, so I'm not going to reinvent the wheel in this post, simply provide the information:

Twitter is a service for friends, family, and co–workers to communicate and stay connected through the exchange of quick, frequent answers to one simple question: What are you doing?

The other really cool thing about twitter is its integration with the Web. While its web interface is nothing to brag about, its Web API is simply amazing. Several programmers have already taken advantage of the API and created several cool applications/modules that should help you integrate twitter into your digital office.

The easiest way to implement the use of Twitter I think, is through the Firefox Extention: Twitterfox. Of course, this would only make sense if you're using Firefox as your main web browser.

Another application is the mentionable Twhirl, built in Adobe Air making it platform independent.

You can find some other dedicated apps and widgets/gadgets on the Twitter Fan Wiki App Page.

For the professional on the go, you'll want some other options if you're computer/laptop/ultra-mobile is unavailable. You can add a mobile device to your twitter settings and send and receive updates via SMS (text messages). Also, if you want to make things even easier you can head over to Dial2Do and have your messages transcribed and posted to your twitter account.

Here is an informational video on Twitter's purpose:
[video:http://www.youtube.com/watch?v=ddO9idmax0o]