As we leave this year behind we’re taking a look at what hit the Twitter headlines this year.

Twitter is fascinating in its ability to reflect what the world is talking about in real time. From the gratuitous to the serious, it is a place to get a real cross section of what people think about current events or what people are outraged, excited, or appalled by. Indeed, in the internet’s 24/7 “outrage economy”, it is the most streamlined way to identify what exactly people are freaking out about—and to get a direct line to celebrities and public figures we want to celebrate or denigrate.

Even though Twitter has only been around since 2008, in those few short years it’s become a more up-to-date news source than the news itself. If a story is developing you’re more likely to find out what’s going on on Twitter faster than a conventional news source. While that doesn’t necessarily mean all the news is going to be true—Tweeters, after all, don’t have to fact check—it does mean that you can watch a news story unfold and read what people are thinking about it like never before.

With 320 million active users monthly (according to Twitter’s year-end report), the service acts as a sounding board for a large swathe of humanity. Interestingly, while most of Twitter’s users are outside the US (79% of active accounts according to the company’s year-end data), most of the trending topics from 2015 centre around events and people within the United States.

A look back at the year’s most tweetable moments almost serves as a recap of the year that just was. With that in mind, here’s a breakdown of who, what and where got people tweeting in 2015:

The most retweets: In 2014, it was Ellen DeGeneres’ epic Oscar selfie that broke the record for most retweets. In 2015 her crown was removed by none other than One Direction member Harry Styles’ well wishes to departed band member Zayn Malik that snagged the top spot, proving once and for all that boy bands wield the most social media sway.

Most popular hashtags: Hashtagging this year seemed to focus on current events. The tragedies in Paris sparked two separate hashtags—#jesuischarlie and #prayforparis—that came to define the awful events themselves, spreading to other social networks and forms of media. The US Supreme Court’s decision to defend the right to marry for gay and lesbian couples also sparked many tweets using the #LoveWins hashtag. Another major moment was in response to a young Muslim American who was accused of bringing a bomb to school (it was really a clock he made himself); #IStandWithAhmed was the response from those who were outraged. Social movement #BlackLivesMatter proved it had Twitter staying power this year too, serving as the hashtag attached to various events of racial injustice and police abuse in the US throughout the year. On a very silly note, the ongoing debate about the colour authenticity of an ugly dress sparked unending controversy, with the #thedress hashtag amassing millions of opinions.

The biggest debuts: Caitlyn (formerly Bruce) Jenner made a splash with her @Caitlyn_Jenner handle after her Vanity Fair cover unveiled her as a woman; the account reached 1 million followers faster than any other account had previously. Equally, NSA whistleblower-in-exile Edward Snowden joined Twitter, immediately garnering thousands of followers with a simple tweet “Can you hear me now?”. He has amassed more than a million followers since then, but he has only followed one account: The NSA, of course. And six years in office, Barack Obama was finally given his own @POTUS account in May, which quickly attracted over 5 million followers.

Happy new year from everyone at UK2! We’re already wondering what will hit the hashtag headlines as we head into 2016…