Tweet Tweet: Robin Roberts Joins Twitter

'GMA' anchor sends first tweet on Twitter's birthday.

March 21, 2011— -- Robin Roberts has entered the "Twittersphere."

Five years after the micro-blogging site Twitter introduced the world to the "tweet," Roberts sent her first 140 character message by tweeting, "I'm finally here! Joining Twitter in honor of you. My way of saying thanks for all your love and support for @GMA."

Follow Robin on Twitter here.

The micro-blogging company launched five years ago on March 21, 2006. The first tweet by company co-founder Jack Dorsey, was simple "inviting coworkers".

Despite Twitter's 140-character maximum per tweet, the service has had an enormous impact on the way people share information.

Since its launch, Twitter has directly influenced change around the world, facilitating the fall of governments and creating a powerful platform for social and political activism.

Unrest in the Middle East – most recently in Libya and Egypt, but going back to 2009 in Iran -- were heavily influenced by the ease with which Twitter allowed participants to share critical information that governments would have suppressed.

It's also allowed many people to have a new voice, and some celebrities – including Charlie Sheen and Gilbert Gottfried – have tweeted their way straight to infamy.

Twitter also has allowed many public figures to bypass traditional media to get their message out directly to followers.On its website the company says it has 175 million registered users, with 370,000 people signing up every day. An estimated 140 million tweets are sent each day, the company said on its blog this month.

The company was founded by Dorsey, Biz Stone and Evan Williams.

In January 2008, Twitter had eight employees. The company now employs 400 people.

Twitter 101: How To Tweet

Step 1: Go to Twitter.com and sign up for an account. It's free.

Step 2: Pick a username. You can do a nickname or a variation of your name.

Step 3: Figure out who you want to follow. You can do a search for celebrities you're interested in getting tweets from, or athletes or politicians, or anyone else who interests you.

Step 4: Whenever you open your Twitter window, you'll start to see the tweets from the people you've chosen to follow.

Step 5: To tweet: Keep it short and sweet. You might want to say something about what's going on in your life or in the news.

Step 6: Many people share links on Twitter, and you can too. If you're going to do that, you might want to shorten the link so it doesn't take up all your allowable space. You can shorten links using Bit.ly (click HERE) or Goo.gl (click HERE). You can also post pictures using Twitpic (click HERE).

Step 7: The lingo: If you see "RT," it means "retweet." That means that the tweet was originally sent by someone else but retweeted, or recirculated, by someone you follow. You can recirculate someone's tweet, too. If you see a tweet you like from someone else, you can click the retweet button and send it out to all the people who follow you.

Step 8: The # sign followed by a word or a phrase is called a hashtag. It link your comment to other comments by uniting them under the same theme. For example, in the wake of the Japan earthquake and tsunami disaster, a popular hashtag has been #prayforjapan.

Step 9: Tweet away!

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