Nearly two decades ago, Facebook exploded on college campuses as a site for students to stay in touch. Then came Twitter, where people posted about what they had for breakfast, and Instagram, where friends shared photos to keep up with one another.

Today, Instagram and Facebook feeds are full of ads and sponsored posts. TikTok and Snapchat are stuffed with videos from influencers promoting dish soaps and dating apps. And soon, Twitter posts that gain the most visibility will come mostly from subscribers who pay for the exposure and other perks.

Social media is, in many ways, becoming less social. The kinds of posts where people update friends and family about their lives have become harder to see over the years as the biggest sites have become increasingly “corporatized.” Instead of seeing messages and photos from friends and relatives about their holidays or fancy dinners, users of Instagram, Facebook, TikTok, Twitter and Snapchat now often view professionalized content from brands, influencers and others that pay for placement.

The change has implications for large social networking companies and how people interact with one another digitally. But it also raises questions about a core idea: the online platform. For years, the notion of a platform – an all-in-one, public-facing site where people spent most of their time – reigned supreme. But as big social networks made connecting people with brands a priority over connecting them with other people, some users have started seeking community-oriented sites and apps devoted to specific hobbies and issues.

“Platforms as we knew them are over,” said Zizi Papacharissi, a communications professor at the University of Illinois-Chicago, who teaches courses on social media. “They have outlived their utility.”

The shift helps explain why some social networking companies, which continue to have billions of users and pull in billions of dollars in revenue, are now exploring new avenues of business. Twitter, which is owned by Elon Musk, has been pushing people and brands to pay $8 to $1,000 a month to become subscribers. Meta, the parent company of Facebook and Instagram, is moving into the immersive online world of the so-called metaverse.

For users, this means that instead of spending all their time on one or a few big social networks, some are gravitating toward smaller, more focused sites. These include Mastodon, which is essentially a Twitter clone sliced into communities; Nextdoor, a social network for neighbors to commiserate about quotidian issues like local potholes; and apps like Truth Social, which was started by former President Donald Trump and is viewed as a social network for conservatives. “It’s not about choosing one network to rule them all – that is crazy Silicon Valley logic,” said Ethan Zuckerman, a professor of public policy at the University of Massachusetts Amherst. “The future is that you’re a member of dozens of different communities, because as human beings, that’s how we are.”

Twitter, which automatically responds to press inquiries with a poop emoji, did not have a comment about the evolution of social networking. Meta declined to comment, and TikTok did not respond to a request for comment. Snap, the maker of Snapchat, said that although its app had evolved, connecting people with their friends and family remained its primary function.

A shift to smaller, more focused networks was predicted years ago by some of social media’s biggest names, including Mark Zuckerberg, Meta’s chief executive, and Jack Dorsey, a founder of Twitter.

In 2019, Zuckerberg wrote in a Facebook post that private messaging and small groups were the fastest-growing areas of online communication. Dorsey, who stepped down as Twitter’s chief executive in 2021, has pushed for so-called decentralized social networks that give people control over the content they see and the communities they engage with. He has recently been posting on Nostr, a social media site based on this principle.

Over the past year, technologists and academics have also focused on smaller social networks. In a paper published last month and titled “The Three-Legged Stool: A Manifesto for a Smaller, Denser Internet,” Zuckerman and other academics outlined how future companies could run small networks at low costs.

They also suggested the creation of an app that essentially acts as a Swiss Army knife of social networks by allowing people to switch among the sites they use, including Twitter, Mastodon, Reddit and smaller networks. One such app, called Gobo and developed by MIT Media Lab and the University of Massachusetts Amherst, is set for release next month.

The tricky part for users is finding the newer, small networks because they are obscure. But broader social networks, like Mastodon or Reddit, often act as a gateway to smaller communities. When signing up for Mastodon, for example, people can choose a server from an extensive list, including those related to gaming, food and activism.

Eugen Rochko, Mastodon’s chief executive, said users were publishing more than 1 billion posts a month across its communities and that there were no algorithms or ads altering people’s feeds.

One major benefit of small networks is that they create forums for specific communities, including people who are marginalized. Ahwaa, which was founded in 2011, is a social network for members of the LGBTQ community in countries around the Persian Gulf where being gay is deemed illegal. Other small networks, like Letterboxd, an app for film enthusiasts to share their opinions on movies, are focused on special interests.

Smaller communities can also relieve some social pressure of using social media, especially for younger people. Over the past decade, stories have emerged – including in congressional hearings about the dangers of social media – about teenagers developing eating disorders after trying to live up to “Instagram perfect” photos and through watching videos on TikTok.

The idea that a new social media site might come along to be the one app for everyone appears unrealistic, experts say. When young people are done experimenting with a new network – such as BeReal, the photo-sharing app that was popular among teenagers last year but is now hemorrhaging millions of active users – they move on to the next one.

“They’re not going to be swayed by the first shiny platform that comes along,” Papacharissi said.

People’s online identities will become increasingly fragmented among multiple sites, she added. For talking about professional accomplishments, there’s LinkedIn. For playing video games with fellow gamers, there’s Discord. For discussing news stories, there’s Artifact.

“What we’re interested in is smaller groups of people who are communicating with each other about specific things,” Papacharissi said.

More small networks are likely on the horizon. Last year, Harvard University, where Zuckerberg founded Facebook in 2004 as a student, began a research program devoted to rebooting social media. The program helps students and others create and experiment with new networks together.

One app that emerged from the program, Minus, lets users publish only 100 posts on their timeline for life. The idea is to make people feel connected in an environment where their time together is treated as a precious and finite resource, unlike traditional social networks such as Facebook and Twitter that use infinite scrolling interfaces to keep users engaged for as long as possible.

“It’s a performance art experiment,” said Jonathan Zittrain, a professor of law and computer science at Harvard who started the research initiative. “It’s the kind of thing that as soon as you see it, it doesn’t have to be this way.”