Why use a desktop application for Twitter?
Desktop Applications allow for easy management and viewing of one's twitter stream, especially for multiple accounts.
Tweetdeck: allows users to see sent, received, follwers/users on twitter
Seesmic Desktop: excellent for multiple twitter accounts
Twitterific: for Mac users
Twuffer: send planned tweets, in the future
Digsby: allows users to open multiple social tools/networking on computer
For the iPhone: 29 Twitter apps for the iphone compared
What is Twitter?
Some refer to Twitter as a microblogging platform. Others think of it as a bar - a place to gather & share information with other like-minded people. It can also be a very good marketing tool.
How Do You Interact With Others On Twitter?
Your friends on Twitter are called Followers.
A general update on Twitter is called a Tweet, which goes out to all of your Followers (and are searchable by any Twitter user, if your profile is not set to "protected").
Tweets must be 140 characters or less.
There are two options for communicating with an individual user:
To forward a tweet is to send a ReTweet (RT). This effectively passes on anothers' tweet to the rest of your followers.
Posting to Twitter and Facebook simultaneously: