Can i send a message on twitter to someone who is not following me?

[Mary S]

will that person see that message and could reply ? and how does it work?

[DAWEI]

You can't send a private message to someone who is not following you, but you can send a message with their user name, for example "@user name the message u want to send"

And hopefully, the recipient uses a desktop twitter software, such as Seesmic, which will notify them when someone mentions their user name