(ABC NEWS) --Seven years ago the first tweet appeared on a then private social networking website. "Just setting up my twttr," Jack Dorsey, the co-founder of Twitter, tweeted on March 21, 2006. Since that day, or really since Twitter's official public launch on July 15, Twitter has exploded, changing the way we interact with people on the Internet and get short bursts of information.
O.K., so its not like your mom's or your best friend's birthday, but that doesn't mean you can't celebrate in your own selfish, tweeting way. In fact, we think Twitter's birthday is a great excuse to spend the day on Twitter. Here are seven things you can do today on Twitter.