Why it matters: Microsoft surprised users with the unveiling of not one but two Surface Pros --- the Surface Pro 7 and Surface Pro X. However, that was not the only thing Redmond had hidden up its sleeve. Adding to the vast Surface lineup, Microsoft introduced the dual-screen Surface Neo at its keynote on Wednesday.

As you may remember, back in 2009, Microsoft revealed that it was working on a dual-screen tablet codenamed Courier. Subsequently, the company nixed the project the following year. Redmond did not completely close the door on the idea saying that the technology might be used in future endeavors. Indeed, rumors swirled in recent years that something was coming.

Those endeavors came to fruition today in the form of the Microsoft Surface Neo due out next year. The device utilizes two 9-inch diagonal side-by-side screens connected with a 360-degree hinge, so it can be used as a small tablet capable of doubling in size. The displays are made from Gorilla Glass, and Microsoft claims that the LCD is "the thinnest ever created."

The screens can be used in tandem as one large display or independently for multitasking. Microsoft said that to make this work, it had to redesign Windows 10, creating a completely new operating system called Windows 10X. The new OS has many capabilities including handing both screens at once, switching orientation when the device is rotated 90 degrees, and more.

If dual screens were not surprising enough, the Surface Neo also has an integrated keyboard. The physical board folds over to cover about two-thirds of the second display. When tucked away, the hardware is held in place to the back of the screen with magnets. The keyboard is also detachable so that you can take advantage of both displays at once.

Interestingly, when using the hardware keyboard, the second display resizes, and the top third is used similarly to the Apple's Touch Bar on MacBook Pros. However, more screen real estate allows it to do much more than the Touch Bar, such as displaying a video while you use the top screen for something else. It can also act as a trackpad for the main display if you move the keyboard to the top part of the second screen.

Microsoft did not go into details about the hardware powering the device, only saying that it uses a custom "hybrid" Lakefield processor with an "11th Gen" graphics engine.

In addition to the Neo, Microsoft also introduced the Surface Duo. The Duo is like a miniaturized Neo, but powered by Android and is meant to be Microsoft's answer to a foldable smartphone. Check out our separate coverage for more information on that device.

Redmond did not have a precise release date or expected pricing to offer for the Surface Neo but did promise that it would be out by 2020's holiday season.