Photograph: Instagram.com/kevin

Before 2010, the internet belonged to cats. Not only could they Has Cheezburger, they ate it, too, as cat memes superimposed with funny broken English captions reigned supreme on the web. Then came the first post on Instagram, on 16 July 2010. App co-founder Kevin Systrom took a picture of a stray dog lying near a taco stand in Mexico and uploaded it with the caption “test”. He was testing the capabilities of his new photo-sharing service, sure, but he was also testing the water for dogs. Since Instagram’s public launch in October 2010, there have been 97m photos hashtagged #dogs on the site, but only 92m hashtagged #cats. Yes, Systrom changed social media as we know it, but when it comes to PR for man’s best friend, his work is unparalleled.

Photograph: courtesy Colette Miller

What do you do when you visit a new city? Try out the local cuisine? Check out the most popular museum on TripAdvisor? If you’re big on Instagram, you might be more interested in walking wall to wall to wall. “Wall crawls” are an incredibly popular tourist activity, as murals and street art have long been considered the best backdrop for interesting #holiday pics. It started in 2013, when artist Colette Miller posted the first Instagram picture of her Global Angel Wings project. In essence: she encouraged artists to paint human-sized wings on walls around the world, which in turn encouraged people to pose in front of them. She aimed to “remind humanity that we are the angels of this earth”; she succeeded in getting your LA holiday snap 150 likes.

Lancelot and Guinevere were born a few hundred years early for Instagram, and Romeo and Juliet never got the chance to put a Lark filter atop their #OOTD posts from the Capulet ball. As such, Kim Kardashian and Kanye West win the award for “the world’s most romantic Instagram photo” after their first kiss as a married couple became the most-liked picture of 2014 (knocking Justin Bieber from the throne). Kim’s post broke records as the first picture to receive more than two million likes, a number the star now achieves on a regular basis. In five years, Instagram has grown from 200 million users to one billion, and the Kardashian-Wests remain our Instagram overlords.

Photograph: Instagram.com/essenaoneill

It’s now firmly established – in PSHE lessons and heartfelt #NoMakeUpSelfies – that social media is not real life. Yet the first person to authoritatively announce this was Australian teenage influencer Essena O’Neill in 2015. After gaining more than 600,000 followers on the site, O’Neill deleted 2,000 images and recaptioned the remaining 96. “I just want younger girls to know this isn’t candid life, or cool or inspirational. It’s contrived perfection made to get attention,” she wrote on an image of herself wearing a bikini, confessing to sucking in her stomach and pushing up her boobs. In being one of the first people to expose the fakery inherent in Instagramming, O’Neill paved the way for conversations – and academic studies – about how the social network affects mental health.

There are many remarkable things that we take for granted in life: the neon pink of an autumn sunset; the trilling of birds on our morning commute. Also underappreciated in its time: Kendall Jenner’s claim that the most-liked Instagram picture of 2015 was “organic”. The picture showed Jenner lying on the ground in a white lace dress, her hair intricately arranged in the shape of seven hearts. The Macmillan dictionary definition of organic? “Happening or developing in a natural and continuous process.” You can’t get much more contrived than getting three supermodels to arrange your hair on a yacht, but c’est la vie, because after Jenner received 3.5m likes, the pose became incredibly popular among copycats. Yacht: optional.

6 The most-fumbled picture (2016)

The concept of influencers who can prompt their followers to purchase products has taken off in recent years; this year Business Insider valued the influencer industry at $8bn. Kim Kardashian allegedly earns up to $500,000 per branded post, so you can’t blame marketers for going with a cheaper option. In May 2016, Kourtney Kardashian’s ex, Scott Disick, accidentally left the instructions from an advertiser in his Instagram caption about a protein shake. “Here you go, at 4 pm est, write the below. Caption: ‘Keeping up with the summer workout routine with my morning @booteauk protein shake!’,” Scott posted for the world to see. Two months later, girl band Little Mix did the same thing in a perfume ad.

Photograph: Instagram.com/genderless_nipples

Launched in 2016, the @genderless_nipple account sought to expose Instagram’s double standards when it comes to female nudity. Since its launch, the social network has been criticised for censoring breasts by removing nude pictures of women, while topless pictures of men remain acceptable fodder for Likes. Three advertising students from New York created this account, which posts zoomed-in pictures of nipples, meaning the identity (and gender) of the owner remains hidden. In December 2016, a male nipple was removed from their page for violating Instagram’s community guidelines; “Why even bother banning female nipples if they can be so similar?” retorted the account. The page now has over 77,000 followers and continues to post nipples. Meanwhile, Instagram’s guidelines remain unchanged, and in October 2019, 20 artists met with the site to ask them to stop the censorship.

8 The most-political picture (2017)

Facebook Twitter Pinterest Photograph: Pete Souza/The White House

On 29 January 2017, former White House photographer Pete Souza posted a picture of former president Barack Obama kneeling at the school desk of a young refugee who was painting a picture. This wasn’t your regular #ThrowbackThursday; Souza was using the image to subtly condemn new president Donald Trump. Two days earlier, Trump had signed an executive order lowering the number of refugees who could be admitted into the United States. Since then, Souza has regularly posted pictures of Obama that contrast with news stories about Trump: when Trump fought with German chancellor Angela Merkel, Souza posted a picture of Obama and Merkel captioned “besties”; when Trump tweeted that his former aide Omarosa was a “dog”, Souza posted a picture of Obama and his family dog Bo, captioned, “A real dog waiting for a real President”.

9 The most-liked picture (2019)

How will history judge us? In the grand timeline of humanity, are we but a blip, or are we a generation that changed the world? None of these questions are answered by the world’s most-liked Instagram (and indeed, internet) post: a picture of an egg. On 4 January 2019, an account named @world_record_egg posted a picture of an egg with the rallying cry: “Let’s set a world record together and get the most liked post on Instagram. Beating the current world record held by Kylie Jenner”. By March, the picture had over 53m likes, and today remains the most-liked on the platform. Was the whole thing a profound statement against consumerism and celebrity? Are we finally reclaiming our identity and autonomy in the (filler-filled) face of Instagram perfection? Or does Jenner still have six of the 20 most popular posts on Instagram? Oh, yeah. It’s that one.

Photograph: aim.os/Instagram

On 18 June 2018, 20-year-old American rapper XXXTentacion was fatally shot during a robbery in Florida. The controversial artist was mourned at a memorial in a South Florida arena – his coffin lay open onstage as thousands of young fans sang his songs in grief – as well as on Instagram, where the final picture he uploaded before his death is believed to be the site’s most commented-on post. Over five million people have left messages on the upside down picture of the topless rapper, and new comments come in every minute. “Miss you”s are interspersed with crying emojis, RIPs, and symbols of broken hearts. There are no official figures for the most commented-on Instagram post, but fans believe XXXTentacion holds the top spot, pointing to it as evidence for his legacy.

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