Every once in awhile, a social media campaign turns into something truly remarkable. Beyond simply going viral, these campaigns…quite simply…break the Internet.

Often, these Internet phenomena occur by pure luck. Other times, they are the result of well-orchestrated campaigns executed by savvy social media marketers.

Here are 5 of the most memorable social campaigns of all time and what made them so successful.

1. The Ice Bucket Challenge

ALS Ice Bucket Challenge
Image credit: The National

It’s not every day that a social media campaign entices 17 million people to post videos on Facebook and also generates $115 million in charitable donations within 6 weeks. The Ice Bucket Challenge was a game-changer. In the summer of 2014, it compelled millions to dump water on their heads, post a video of it online and challenge friends to do the same in lieu of a $100 donation to the ALS Association (many donated anyway).

Here’s the interesting part: the campaign wasn’t organized by ALS. In early versions of the challenge, participants selected the charity of their choice. But after a well-known ALS advocate shared the challenge with his large social network, it became permanently associated with the ALS Association. The organization acted quickly to take ownership of the campaign. The challenge is now an annual fundraising event for the company.

2. Kony 2012

Kony 2012
Image credit: NPR

In 2012, a little-known non-profit group posted a 29-minute video on Vimeo about a Ugandan war criminal. By the end of the next week, it had become the fastest-growing viral video of all time, racking up over 100 million views in 6 days.

The New York Times attributed the video’s success to its powerful simplicity. It had a clear call to action: share the video to raise awareness of Joseph Kony worldwide to aid in his capture, and encourage celebrities to do the same. It worked. Within the first week, the video had been shared by many high-profile figures, including Oprah Winfrey, Mia Farrow and Bill Gates.

3. The Old Spice Guy

old spice
Image credit: LA Times

When in doubt, go zany. That’s what Proctor & Gamble did in 2010 when deciding how to reintroduce their iconic Old Spice brand. It released a commercial starring a comically straight-faced Isaiah Mustafa, standing in a towel, telling viewers to “Look at your man. Now back at me. Now back at your man. Now back to me.” The ad became an Internet sensation, racking up over 13 million views. It later aired on television.

Aside from the sharable “weird” factor of the video, the campaign worked so well because of the way the company leveraged social media to connect directly with their audience. According to AdWeek, “the real success of the campaign came when Old Spice launched their response campaign, in which [the Old Spice Guy] interacted with fans” via Twitter and other platforms.

4. Dollar Shave Club

Dollar Shave Club
Image credit: YouTube

If you spent any time on social media in 2012, then you probably saw the 90-second video for a new razor blade business called Dollar Shave Club. A seemingly straightforward ad at first, it featured the company’s founder Michael Dubin, who says to viewers: “Are the blades any good? No. Our blades are [expletive] great.”

Much like The Old Spice Guy, this campaign was a hit for its sheer cheeky value. Dubin told the New York Times that more than 12,000 orders were placed within the first 48 hours of releasing the video. By the next year, the video had been viewed 10 million times.

5. Like a Girl (Always)

Like a Girl
Image credit: Marketing Week

Procter & Gamble had another social media hit on its hands in 2014 with its “Like a Girl” video, which became the company’s most watched video in history with more than 76 million views. But unlike the company’s zany Old Spice campaign, this one broached more serious issues of gender stereotypes and empowerment. A promotion for Always, the video was widely shared on social media and became a fascinating case study on how to make a female hygiene brand go viral.

The success of this campaign lies partly in its social experiment guise. It engages viewers by showing women of different ages being questioned in front of cameras on what it means to “run like a girl” or “fight like a girl.” And just like that, the Like a Girl video (and #likeagirl hashtag) took off. The video was also re-released in 2015 as a Super Bowl ad.

What’s your favorite campaign? What brand do you think will be next with a breakout social media campaign? Who do you think missed a prime opportunity? Share your thoughts in the comments.