Known for its short-form videos popular with teens, TikTok has become a global social media sensation, and at the same time has found itself at the heart of a geopolitical war between the United States and China.

US President Donald Trump has called the app a national security risk, claiming that TikTok and its Chinese parent ByteDance could access user data and deliver it to Chinese intelligence services.

Trump's executive order would prohibit new downloads of TikTok from Sunday night and would ban usage from November 12 unless a deal to restructure its ownership comes to fruition.

TikTok has seen some two billion downloads and its user base is estimated at 700 million, making it one of the biggest players in the social media space.

TikTok's short-form video app has become one of the world's most popular social media platforms
TikTok's short-form video app has become one of the world's most popular social media platforms AFP / Lionel BONAVENTURE

It is known for its user-generated short videos of 15 to 60 seconds, many featuring dancing, parodies or comments on the news. Filters and special effects can be added.

The coronavirus pandemic has helped TikTok expand its user base beyond young smartphone users, as new kinds of content are added and popular "influencers" join the platform.

Created in 2016 as Muscal.ly, the app was acquired by ByteDance in 2017 and rebranded as the global version of the Chinese app known as Douyin.

According to the company, TikTok has 100 million users in the United States alone, with 50 million logging on every day. Before July, when reports of a ban began to circulate, TikTok was adding some 400,000 US users every day.

While its quirky videos seem innocuous, TikTok has drawn scrutiny over potential security threats.

TIkTok is at the center of a political dispute pitting US President Donald Trump against China, whose president Xi Jinping is seen at right
TIkTok is at the center of a political dispute pitting US President Donald Trump against China, whose president Xi Jinping is seen at right AFP / Brendan Smialowski

Republican Senator Marco Rubio called in 2019 for an investigation in TikTok's links to Chinese authorities, and in 2020 the Defense Department told all its personnel to remove the app.

TikTok has denied ties to the Chinese government and claims its servers are inaccessible to Beijing.

"We store all US user data in the United States, with backup redundancy in Singapore," TikTok said in a recent statement.

"TikTok's data centers are located entirely outside of China."

But a White House executive order in August claimed TikTok "automatically captures vast swaths of information from its users," and that this "threatens to allow the Chinese Communist Party access to Americans' personal and proprietary information."

This, according to the White House, could allow China to "track the locations of federal employees and contractors, build dossiers of personal information for blackmail, and conduct corporate espionage."

Trump has sought to take TikTok out of Chinese control, and has given his blessing to a deal that would make Silicon Valley giant Oracle the data partner for the application.

It remained unclear if Beijing would approve the deal, terms of which remained somewhat murky.

One of the key details is what would happen to the TikTok recommendation algorithm seen as the key to its success. The system uses machine learning to determine user preferences and deliver videos to keep people engaged, without too much repetition.

China last month issued new rules that would prevent the export of algorithms and artificial intelligence technologies.

ByteDance has claimed it would maintain control of the algorithm while Oracle would merely be able to inspect the data and source code for security flaws. Trump has said he would not accept any deal that leaves the Chinese in control of TikTok.