TIMELINE OF TWITTER'S HEADLINE-GRABBING 10 YEARS
* 2006: Co-founder Jack Dorsey tweeted first, when the service was called "Twttr".
* 2007: Early user Chris Messina proposed the use of a hashtag to denote people at the same live event.
* 2008: When the Mars Phoenix Lander found ice on Mars, Nasa used Twitter to break the news.
* 2009: Early user Janis Krums happened to be on a ferry when a plane went down in the Hudson River.
* 2010: In a royal first, Clarence House, the Prince of Wales' private office, created a Twitter account to announce Prince William's engagement to Kate Middleton.
* 2011: Up late one night, Sohaib Athar inadvertently tweeted about the secret raid on Osama bin Laden's compound in Pakistan.
* 2012: Before he appeared publicly to affirm his second presidential win, US president Barack Obama noted it on Twitter. And within hours it became the most retweeted of the year.
* 2013: Two bombs shook the Boston Marathon - and the world. As news of the blasts and the manhunt spread, Twitter became crucial for journalists, police and citizens alike.
* 2014: The #BringBackOurGirls movement was created when more than 250 schoolgirls were abducted in Chibok, Nigeria, by Boko Haram militants. Federal minister Oby Ezekwesili led the declaration of the #BringBackOurGirls hashtag.
* 2015: As the horrific attacks in Paris unfolded in November, the world united to support people in the City of Light using the hashtag #PrayForParis. Just 10 months prior, terrorists attacked the Paris offices of satirical magazine Charlie Hebdo. After that incident, citizens rallied around the phrase Je Suis Charlie to show their support and sorrow for the victims.
* 2016: #Oscars: Leonardo DiCaprio's win for best actor in The Revenant generated 440,000 tweets a minute, more than @TheEllenShow's selfie two years earlier.