It is a website where we make short (140 character) messages. We can send them by SMS, on the website and/or using client apps (like LJ clients but twitter clients instead). It is an even easier way of keeping people updated with how you are and what you are doing than sitting at a keyboard and posting on LJ. You can also *receive* tweets on your cellphone by SMS (all of your friends, some of your friends and/or just direct messages).
The Twitter FAQ.
I hope that explains it well enough!
My NaBloPoMo Profile
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