Twitter released its round-up of the most influential and popular tweets of 2014 Wednesday, a chance to reflect on a year of celebration and sadness, solemnity and humor.

The year’s most visible tweet, recognized by Twitter as the “Golden Tweet,” occurred during the Oscars telecast in March, when host Ellen DeGeneres posed for a selfie featuring a slew of celebrities, including Jennifer Lawrence, Bradley Cooper, Meryl Streep, Kevin Spacey, Brad Pitt and Angelina Jolie.

The tweet has been retweeted 3.3 million times.

Some of the key topics highlighted on Twitter in 2014 involved the World Cup, #BringBackOurGirls in response to kidnapped schoolgirls in Nigeria, and #BlackLivesMatter, with more than 18 million tweets about unrest in Ferguson, Missouri, after Michael Brown was shot and killed by a police officer in August.

Other notable topics included #MH370, the search for a missing Malaysia Airlines plane; the Sochi winter Olympics; the death of performer Robin Williams; and protests in Hong Kong.

First lasy Michelle Obama showed support for the kidnapped Nigerian schoolgirls.

A popular image showed soccer teammates Lukas Podolski and Bastian Schweinsteger celebrating Germany’s World Cup victory.

News of an impending royal birth was also popular.

The Ebola outbreak drew international attention across social media.

The Philae Lander revealed the stunning view from the surface of a comet.

And Pharrell’s hat at the Grammys served as a cultural breakout moment.