The power of the hashtag was at full tilt on Twitter this year, amplifying some of the most important news stories and helping give rise to social movements at home and abroad.
Thanks to social media, people around the globe shared those stories — sometimes finding common ground and creating a place to grieve or give back.
Here's how the top 10 trending hashtags of the year, according to Twitter, made an impact — sometimes amid controversy:
As a platform for sharing information, Twitter remains rife with people posting about employment or seeking advice about work. The generic #jobs has become a widely used hashtag — so much so that it was cited the most of any this year.
Islam's holy book is part of a larger discussion about the Muslim faith, which remains a prominent topic of online conversation, in part, because of the issue of religious extremism.
The killing of 130 people across several sites in Paris on Nov. 13 shocked the world for its brutality. ISIS has claimed responsibility for the massacre. Meanwhile, #PrayforParis has given people a way to mourn and show kinship with those in pain.
Masked gunmen stormed the Paris offices of the satirical French magazine, Charlie Hebdo, on Jan. 7, killing a dozen people. The shocking massacre — linked to two Islamic extremist brothers — drew attention to the magazine, which published controversial cartoons of the Prophet Muhammad.
In a show of solidarity for the magazine, the #JeSuisCharlie ("I am Charlie") movement brought together not only France but the world.
The movement emerged last year after high-profile police shootings of unarmed black men. It has since become a rallying cry surrounding incidents involving race relations, and a way for people to agitate for police and government reform. It also spawned similar "lives matter" hashtags.
9. #地震 [Earthquake]
This hashtag represents the thousands of tweets in response to several major natural disasters in 2015. This year, Japan experienced quakes that were magnitude-5.0 and higher, particularly in May.
Texas woman Sandra Bland was found dead in an apparent suicide in her cell in July, three days after her arrest in a routine traffic stop. Her death was puzzling — and some say suspicious. It led to state and federal investigations involving police. Social media activists, who promoted the hashtag, joined together to call for the investigations.