The Ultimate Twitter Quiz

Twitter began as a side project for a startup company in March of 2006.

Jack Dorsey got the idea for Twitter when he wondered if someone could build a simple but interesting application that would let a person know what his or her friends were up to at any given time.

Twitter's valuation reached $1 billion in September 2009. That's staggering for a company that was famous for not having a clearly-defined business plan.

Ashton Kutcher threw down the gauntlet in 2009, challenging CNN in a race to 1 million followers. Ashton won the unofficial contest.

The Twitter "fail whale" showed up often during Twitter's first growth spurt. Along with a brief message about the service being down, the page shows a cheerful whale supported by birds.

The Shorty Awards go to the best Twitter users in categories like tech and music. The Twitter community nominates and votes for the users they like best.

Nielsen Wire said that only 40 percent of Twitter users stuck with the service. The other 60 percent gave Twitter a try but abandoned it soon after.

The original prompt said "What are you doing?" Perhaps Twitter changed the message after too many people typed "I'm using Twitter."

James Karl Buck twittered the word "arrested" as Egyptian police took him into custody. Friends and colleagues were able to contact U.S. authorities who arranged Buck's release.

Mike Massimino, aka astro_mike on Twitter, sent the first tweet from space. His message read "From orbit: Launch was awesome!! I am feeling great, working hard, & enjoying the magnificent views, the adventure of a lifetime has begun!"