For the past five years, China has had the world’s fastest computer. But as of Friday, Summit, a machine built in the United States, is taking the lead.

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The United States just won bragging rights in the race to build the world’s speediest supercomputer.

For five years, China had the world’s fastest computer, a symbolic achievement for a country trying to show that it is a tech powerhouse. But the United States retook the lead thanks to a machine, called Summit, built for the Oak Ridge National Laboratory in Tennessee.

Summit’s speeds, announced on Friday, boggle the mind. It can do mathematical calculations at the rate of 200 quadrillion per second, or 200 petaflops. To put in human terms: A person doing one calculation a second would have to live for more than 6.3 billion years to match what the machine can do in a second.

Still stupefying? Here is another analogy. If a stadium built for 100,000 people was full, and everyone in it had a modern laptop, it would take 20 stadiums to match the computing firepower of Summit.

China still has the world’s most supercomputers overall. And China, Japan and Europe are developing machines that are even faster, which could mean the U.S. lead is short-lived.

Supercomputers like Summit, which cost $200 million in government money to build, can accelerate the development of technologies at the frontier of computing, like artificial intelligence and the ability to handle vast amounts of data.

Those skills can be used to help tackle daunting challenges in science, industry and national security — and are at the heart of an escalating rivalry between the United States and China over technology.

For years, U.S. tech companies have accused China of stealing their intellectual property. And some Washington lawmakers say that Chinese companies like ZTE and Huawei pose a national security risk.

Supercomputers now perform tasks that include simulating nuclear tests, predicting climate trends, finding oil deposits and cracking encryption codes. Scientists say that further gains and fresh discoveries in fields like medicine, new materials and energy technology will rely on the approach that Summit embodies.

“These are big data and artificial intelligence machines,” said John E. Kelly, who oversees IBM Research, which helped build Summit. “That’s where the future lies.”