It was another big year for Twitter. There were so many events, so many moments that resonated with the nation and beyond. But here are five of the most memorable.

1. The #hashtags from the terror attacks in Paris.

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In aftermath of the terror attacks that killed 129 people in Paris, the whole world came together on social media to stand in solidarity with the French capital. Within hours of the attack — and in the days following — the hashtag #PrayForParis started trending worldwide. The hashtag became a worldwide statement that not only represented support of France, but also peace and humanity.

Related: How Paris responded to the terrorist attacks

Also, the hashtags #NotInMyName and #TerrorismHasNoReligion set the groundwork for fighting the wave of Islamophobia that would soon sweep across the world. As the fear of Islamic terrorism remains alive today, people have continued to use these hashtags to separate themselves from the horrible terrorists acts committed in the name of religion.

2. Caitlyn Jenner's debut on Twitter.

The trans community and Caitlyn Jenner have had a pretty awesome year. She was just named Barbara Walters' Most Fascinating Person of the Year for 2015 and came in at number seven on Time's Magazine's short list for 'Person of the Year.' But before this, she made her debut on Twitter in June, and the Internet rushed to support the most high-profile trans woman in America. Within just four hours of her first tweet, she had one million followers—shattering the record that President Barack Obama set when he first joined Twitter.

Related: The 6 Most Outrageous Anti-Caitlyn Jenner Memes

3. President Barack Obama stands with Ahmed.

AP/Andrew Harnik - apimages.com

Fourteen-year-old Muslim student Ahmed Mohamed was the subject of a racial profiling case that made national headlines. Mohamed was arrested at school and suspended three days after teachers and police in Irving, Texas, assumed that his homemade clock was a bomb. Social media users quickly created the hashtag #IStandWithMohamed to support Mohamed and combat the Islamophobia that many suspected was at play in the case.

But the ultimate support came from President Obama, who tweeted an invitation to Ahmed to bring his clock to the White House.

Related: This Viral Photo Campaign for Ahmed Mohamed is Genius

4. #LoveWins and #MarriageEquality

This year has also been historic for the LGBT community as whole. In June, the U.S. Supreme Court ruled that all bans on same-sex marriage were unconstitutional, thus legalizing gay marriage in every state. Within minutes, the Twitterverse and social media exploded in celebration with the hashtags #LoveWins and #MarriageEquality.

Related: Here's How Much Money Gay Marriage Will Make the Wedding Industry

5. McKinney police incident.

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Social media responded in a big way after a video surfaced of a McKinney, Texas, police officer's rough handling a 15-year-old, Black girl in a bathing suit. The officer, Eric Casebolt, also pulled his gun during the incident, which was spurred by a call to police to deal with unruly teenagers at a pool party in the Dallas-Fort Worth suburb.

Related: Texas Cop Suspended After Pulling Gun On Black Teens At Pool Party

The video only validated growing concerns about race relations and police brutality.