How TikTok grew from a fun app for teens into a potential national security threat

If it feels like TikTok has been around forever, that's probably because it has, at least if you're measuring via internet time. What's now in question is whether it will be around much longer and, if so, in what form?

Starting in 2017, when the Chinese social video app merged with its competitor Musical.ly, TikTok has grown from a niche teen app into a global trendsetter. While, of course, also emerging as a potential national security threat, according to U.S. officials.

On Wednesday, President Joe Biden signed legislation requiring TikTok parent ByteDance to sell to a U.S. owner within a year or to shut down. It's not clear whether that law will survive an expected legal challenge or that ByteDance would agree to sell.

Here's how TikTok came to this juncture:

March 2012

ByteDance is founded in China by entrepreneur Zhang Yimin. Its first hit product is Toutiao, a personalized news aggregator for Chinese users.

July 2014

Startup Musical.ly, later known for an eponymous app used to post short lipsyncing music videos, is founded in China by entrepreneur Alex Zhu.

July 2015

Musical.ly hits #1 in the Apple App Store, following a design change that made the company's logo visible when users shared their videos.

2016

ByteDance launches Douyin, a video sharing app for Chinese users. Its popularity inspires the company to spin off a version for foreign audiences called TikTok.

November 2017

ByteDance acquires Musical.ly for $1 billion. Nine months later, ByteDance merges it with TikTok.

Powered by an algorithm that encourages binge-watching, users begin to share a wide variety of video on the app, including dance moves, kitchen food preparation and various “challenges” to perform, record and post acts that range from