The usual phrase used is "DM" which means "Direct Message"
"DT" is probably similar to this and means "Direct Text"
RT mean "Re-tweet" It's for twitter
Tweet is like status updates or reply to posts on facebook!
Someone wants to chat with you on Twitter.
it means last tweet
Re tweet
it means you are quoting someone else's tweet on Twitter or exactly like it says "re tweeting" tweeting it again.In Short,it means forwarding any other person's tweet to your followers.It is like forwarding text messages or emails.
It means your tweet has been successfully sent.
Sub is used on Twitter when you are referring to someones tweet but you don't actually retweet the tweet in question. It's mainly used when everyone understands who you are referring to.
According to the official Twitter Help Center a mention is "any Twitter update that contains "@username" anywhere in the body of the Tweet".Users will often see hundreds or thousands of tweets a day in their Twitter feed. Mentioning a user in your tweet means they will be able to see it in their "@ Connect" section on the top of the Twitter page.You would usually mention a user if you are directing the Twitter update (tweet) to that specific user OR you want them in particular to see this tweet.If you include more than one @username in your tweet, all of those users will see the Tweet in their "@ Connect" section.
This is the location the tweet was posted from.
tweering is when someone like Perez Hilton tweets on his Twitter page - "tweet" + "queer" = "tweer"
You may send a tweet (or @reply) to anyone on Twitter; you certainly don't have to be following them! Following a Twitter user just means that all their tweets appear in the "timeline" on the home page of Twitter when you log in. (Along with your tweets and the tweets of anyone else you may be following.) To follow someone, go to their Twitter page and click the "follow" button. Anyway, to send a tweet to any Twitter user, just include an @ sign followed by the username of the user you want to send the tweet to. For example, if you want to send a tweet to the user with the username JohnSmith, include @JohnSmith in you tweet.