When Apple unveiled the iPhone X at its Apple Park press event on Tuesday, the company went out of its way to make clear it’s pronounced iPhone “ten” and not iPhone “ex.” Even in the ad the company showed during the show, it made clear that it’s selling the iPhone “ten” and not the “ex.”

If this sounds familiar, it’s because Apple has been at the epicenter of the X controversy for years.

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When Apple (AAPL) started selling its Mac OS X desktop operating system in the early 2000s, there was some debate over whether the X at the end of its name was pronounced like the number or like the letter. And try as it might to say it was the number, many people clung to the letter pronunciation.

Last year, with the release of macOS Sierra, Apple decided to change the name on its desktop operating system. Apple said at the time that it made the change so its operating system would match its other naming conventions, like iOS, tvOS, and others. But it also put the X debate to rest.

That is, until now.

But there really is a right way to pronounce iPhone X. So don’t lose this debate or try to justify your desire to call the iPhone X the iPhone “ex” because you think that’s how it should be said. The almighty Apple has spoken. And from this point forward, iPhone X shall be known as the iPhone “ten.”