For the first time ever, a quantum computer has performed a computational task that would be essentially impossible for a conventional computer to complete, according to a team from Google.

Scientists and engineers from the company’s lab in Santa Barbara announced the milestone in a report published Wednesday in the journal Nature. They said their machine was able to finish its job in just 200 seconds—and that the world’s most powerful supercomputers would need 10,000 years to accomplish the same task.

The task itself, which involved executing a randomly chosen sequence of instructions, does not have any particular practical uses. But experts say the achievement is still significant as a demonstration of the future promise of quantum computing.