How does Twitter work?

[kyle]

i just got a Twitter and im confused as to how it works.

say i'm following kim kardashian it shows this:

Celebration time! @EvaLongoria thank you everyone! beautiful day in miami with @tp9network, @lorenridinger, @kimkardashian, @robinantinpcd!
about 8 hours ago via TweetGenius
RT @robinantinpcd Happy birthday @evalongoria ! Having breakfast in Miami w eva, @kimkardashian all the beautiful girls!!
about 8 hours ago via TweetGenius
Happy birthday @EvaLongoria Can't wait for tonight!!!
about 8 hours ago via TweetGenius
Hurry, we are all here! RT @lorenridinger Gonna go home and see my girls soon @evalongoria @kimkardashian
about 22 hours ago via TweetGenius

stuff like that,,,what does all that mean??
like how do you know who posted what?

[Opt to Opine]

Well, do you see that every so often the string "about X hours ago via TweetGenius"? That signals the end of a particular message.

[cheryleene <3]

@USERNAME is like writing 'to' on a letter; it starts the message when it's the first word in it. But, if it's in the message, it just links to the person's twitter account.
RT, or ReTweet, is basically sharing what someone wrote by showing it on your account. So if person A were to tweet 'Hi' and person B clicked on ReTweet, then it would show up on their profile and be shared with their followers.
About __ hours ago just shows what time it was submitted, and via ___ is where it was tweeted from; there's a lot of sites like TwitPic that are used as applications.. You use them to Tweet on another site.

[NoAnswer]

little blue birds carry the message in their beaks and fly to the person that you addressed the tweet to.
That's how twitter works.

The @ sign is like a "to" in a letter. You can address a tweet to a specific person.