How do you know people are online on Twitter?

[Jessi=D]

I am following 8 people but how do I know if there online? Help please!! I just joined Twitter and I dont know a lot bout it.

[unlimited1010]

You do not know, however there is a third party software that will in fact post your tweets for you and it it will only post it when your follower logs in. This way your message always gets in front of them!

It also does mega other things

Read the article in the link below and follow the step by step instructions.
Twitter is a cash cow. Learn how to hundreds of thousands of followers fast!

[Boboo]

You don't know, there is no way of knowing if they are online. It's not really the idea of twitter either, Twitter is a microblog, or a status updating social networking site in which you make friends and follow people, or get followed by people. And when your network grows bigger you can have your voice heard by many people in your friends networks too...
You blog or tweet with messages of no more than 140 characters. Things to be tweeted (= sending out a twit or tweet (message) on twitter) can be
what you are thinking or doing right now
a new post on your blog that you wrote
a ReTweet (RT) from someone else, think of it as a forward in email