What is twitter i have no clue!?

[Rainbow]

It is yet another Social Networking site like myspace or facebook, how ever it is more similar to facebook because you update your status regularly, and they call it blogging.

You can "follow" other peoples blogs, and people can follow your blog without a request being sent. However if you decide you don't want someone "follow" you, you block them. They won't be notified. Your profile homepage says how many people you are following, and how many are following you.
This is why celebrities get into it, because anyone can follow any celebrity they like without needing approval from that celebrity.

And additionally, like any other social networking site, you can update your profile, add photos, interact with friends etc.
But the main thing that sets it apart is that you can blog more easily. It is more a fan site, than for personal communication.