Sure, sometimes you might want to let everyone know about how you're standing in line to get coffee, but Twitter has become what Time calls a "medium of the movement," growing as an important communication tool and way to quickly network people and information. Twitter has a few things in its favor to make it so. It's free and it's available on more than one mobile platform, including the Internet, instant messaging and SMS. This combination has sparked users to go beyond the coffee talk.
In 2009, for example, Iranians used Twitter to organize government protests -- and in 2008, twitterers kept the world updated on the attacks in Mumbai. They did so by creating searchable tags, such as the hashtag #Mumbai, on Twitter to get the word out around the world.
Find out more about Twitter on the next page.