The Internet gets a lot of flack for providing a haven for the trolls who would tear women down. And while it’s true that there are plenty of sexist jerks online, the digital world also gives women a platform where they can connect, cheer each other on, and call out bad behavior wherever they encounter it.

2015 proved to be an especially fertile year for women on the web. We saw a host of feminist viral sensations—some funny, some serious, but all extremely effective in stoking the conversation about gender equality.

Here, a look at five of our favorites.

1. #ILookLikeAnEngineer

Isis Wenger, founder of the #IlookLikeAnEngineer movementPhotograph courtesy of Isis Wenger

The viral hashtag #ILookLikeAnEngineer began with Isis Wenger, a 22-year-old engineer at San Francisco-based OneLogin, and spread to such high-profile women as GM CEO Mary Barra, No. 1 on Fortune‘s ranking of the Most Powerful Woman in business. The hashtag was born when Anchalee, who appeared in a recruitment ad for her employer, received social media backlash because she didn’t “look” like an engineer. In response, she wrote a Medium post about the experience, inviting others to use the hashtag to help spread the message that engineers come in all genders, races and ages. The rest, so to speak, is history.

2. To Apple, Love Taylor

Taylor Swift '1989' World Tour - Sydney Taylor Swift performs during her ‘1989’ World Tour at ANZ Stadium on November 28, 2015 in Sydney, Australia.Mark Metcalfe Getty Images

It’s pretty easy to go viral when you’re a pop star with more than 67 million followers on Twitter and 50 million-plus Instagram fans. But this year, Taylor Swift proved that its possible to use that popularity to actually make change, when she wrote a letter to Apple APPL on her Tumblr, explaining her plans to withhold her new album, 1989 from the company’s music streaming service. Her reasoning: Apple Music did not plan to pay artists for the three-month free trial. Less than 24 hours after the letter went live, the company backtracked; Apple exec Eddy Cue announced on Twitter that artists would be paid during the trial period.

3. Amy’s apologies

The 74th Annual Peabody Awards Ceremony - Arrivals Comedian Amy Schumer attends The 74th Annual Peabody Awards Ceremony at Cipriani Wall Street on May 31, 2015Photograph by Jemal Countess—Getty Images

2015 was the year of Amy Schumer. Her brand of humor touched a collective nerve, bringing to light the countless small and large slights women cope with daily—both those imposed upon us and those we bear much of the responsibility from bringing on ourselves. With her sketches and public appearances racking up millions of YouTube views and two Golden Globe nominations for Trainwreck, her first starring role in a feature film, Schumer’s success is a reflection of what Hollywood needs: more women.

4. #SmartGirlsAsk

2014 Winter TCA Tour - Day 2 Amy Poehler speaks onstage during the ‘Comedy Central – Broad City’ panel discussion at the 2014 Winter Television Critics Association tourPhotograph by Frederick M. Brown—Getty Images

At this year’s Emmy awards show, female celebrities fielded fewer red carpet questions about who they were wearing, and more questions about their careers. The force behind that shift: Smart Girls, an online community founded by comedian Amy Poehler and dedicated to empowering young people to be their “authentic selves.” In the lead-up to Emmys, the group took to Twitter to ask users to tweet questions they actually want to hear answers to, along with the hashtag #SmartGirlsAsk. The campaign took off, garnering tweets from celebrities, fans and powerful women such as Democratic presidential candidate Hillary Clinton, General Motors CEO Mary Barra, and Hollywood bigwig Shonda Rhimes.

5. Lawrence in Lenny

NEW YORK, NY - NOVEMBER 18: Jennifer Lawrence attends "The Hunger Games: Mockingjay- Part 2" New York Premiere at AMC Loews Lincoln Square 13 theater on November 18, 2015 in New York City. (Photo by Jamie McCarthy/Getty Images) *** Local Caption *** Jennifer Lawrence Jennifer Lawrence attends “The Hunger Games: Mockingjay- Part 2” New York Premiere on November 18, 2015Photograph by Jamie McCarthy—Getty Images

Jennifer Lawrence is the highest-paid actress in Hollywood, but that doesn’t mean her salary is on par with that of her male counterparts. With her personal essay in Lena Dunham’s newsletter Lenny Letter (fittingly titled “Why Do These Dudes Make More Than Me?”), she brought the country’s percolating conversation about the gender wage gap to a boiling point.

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