Snapchat has long thumbed its nose at social-media conventions. The messaging app initially emphasized posts that disappeared. It encouraged users to connect with just a few friends instead of many. And it prized human editing and curation instead of encouraging everybody to post anything.

On Wednesday, its parent company, Snap, continued that unconventional approach, unveiling a redesign that effectively separates social and media into two parts of the Snapchat app.

Where users of Facebook see one giant news feed of information, typically determined by what they have liked and what their friends post, Snapchat users will now see, on the left side of the app, chats and stories shared with, or by, their friends. That’s the social part. The right side will show content from publishers, amateur creators, celebrities and stories that Snap curates from user-generated videos and photos. That’s the media part.

“While blurring the lines between professional content creators and your friends has been an interesting internet experiment, it has also produced some strange side effects (like fake news) and made us feel like we have to perform for our friends rather than just express ourselves,” Evan Spiegel, Snap’s chief executive, said in a blog post about the redesign, which was rolled out through the end of last week.

The redesign is partly born of necessity. Since Snap went public in March, its user and revenue numbers have not grown as fast as Wall Street had hoped. That is partially because of Snap’s chief rival, Facebook, which has sought to keep users from turning to Snapchat by copying some of its most popular features.

Snap’s stock has fallen below its initial public offering price, and the company still hasn't made money. Snap delivered a disappointing earnings report in November, causing its stock to plunge even further.

Some things about Snapchat are not changing. For instance, the app still opens to the phone camera, allowing users to make and share photos and videos with friends.

But the redesign otherwise moves Snapchat even further away from a traditional social media model.

Material shown on the app’s right side — now the media part — must meet content and community standards, Snap has decided, whether that material is produced by a news organization, a television studio, the company’s in-house news and stories teams or so-called influencers. All must be vetted and approved by Snap.

By contrast, those who create content do not need to be vetted to distribute it widely on Facebook and Google. That has allowed hate speech, fake news and disturbing videos to proliferate on those platforms. During the presidential election last year, Russian propagandists used Facebook, Google and Twitter to spread material meant to sow division and influence the outcome of the race.

“Separating social from media has allowed us to build the best way to communicate with friends and the best way to watch great content — while addressing many of the problems that plague the internet today,” Spiegel said in his blog post.

Philip Napoli, a professor of public policy at Duke University who studies media and democracy, said Snapchat’s redesign would test people’s willingness to embrace a social media app that relied more on human curators than algorithms.

“It wouldn’t surprise me if there’s enough of a consumer backlash to make this potentially viable, especially in light of the last year,” Napoli said.

Snap said it was using machine learning to understand what people like to see, based on their activity, and planned to offer them new content in line with those preferences.

There are limits to the amount of personalization that Snapchat will provide. In an approach similar to how Netflix widely promotes some television shows and movies, Snap will continue to promote some material — including breaking news, a new video series or a popular sporting event — to all of its users.

Human curators will also program content to make sure that users’ preferences are not keeping them from seeing a wide array of opinions and ideas, the company said. In addition to winnowing out fake news, this may keep Snapchat from becoming a place that reinforces narrow thinking.