Twitter is a computer program that lets you send messages to lots of people all at the same time, provided those people have all agreed to accept messages from you. These people are called “followers”.
Twitter is NOT the same as email because your followers cannot reply to you, and it is NOT the same as Facebook, where people only get your full message if they log into their own Facebook account to see their feed, though it has elements that are the same.
Twitter lets you send short messages. These are called Tweets. A tweet was originally allowed a MAXIMUM of 140 characters, including spaces to get a point across, however, this has now been doubled for most users to 280 characters. Some people take advantage of this, others don’t.
The previous paragraph contains exactly 280 characters, including spaces, so that’s how much you can write in one tweet. The tweet needs to contain ALL the information you want to send, including a web address, if you want the tweet to tell people to visit a certain web page.
You have to be registered with Twitter to send messages. Once you are a registered user, any messages you send go out to ALL your followers at the same time, not just to one or two people that you choose.
A tweet is meant to give your followers a “heads up” to something important that they can read about elsewhere, such as a piece of news, or it might just give them information that they may find interesting, for instance, if you are a celebrity, your followers may want to know what you had for breakfast!
Getting followers can be tricky because people have to know that you are on Twitter and they have to get to know your username and decide to follow you. If you follow people, some of those will follow you back, but not all. Twitter itself provides suggestions of people for you to follow and thus can suggest you to others. There are various strategies you can use to get followers. BarbRad suggests a good way to start is to write a really good Twitter profile http://personapaper.com/article/11098-how-to-build-your-twitter-following so that anyone who checks it out will be able to see your interests and decide if you are worth following. She covers what she expects to see in a Twitter profile and also gives other useful information on links, quality Tweets and obtaining a balanced Twitter feed.