[J-Rock]

Off topic (sort of)....Can someone just tell me - when you've first signed up to twitter - how do you send a message to someone.

E.g. @username - then your message...in the box where it says 'What you doing?'

Do they then automatically receive it if you're following them, or do they have to accept you first or something?

I have tried to read the instructions.....

Any advice - please - thanks!