Here's the guide how to use and know Twitter's command.
@username When you go mention someone, you can use this command.
D username or DM username This is working like private message and is called Direct Message. DM is only working if you send it to someone who follow you.
RT @username A Re-Tweet. It means a re-broadcast for tweet. Prefaced with the original twitterer's username.
WHOIS username Give you information about specified user.
GET username Get most recent tweet of an user.
FOLLOW username Twitter display dropdown message with tweet message from people you follow, if you want certain people's tweet written on your own dropdown message, you need to follow them. Use FOLLOW.
LEAVE username By use this command, you will not able to read tweet peolpe you leave (unfollow).
