Microsoft has unveiled a lot of interesting things in its Jan. 21 Redmond event. While many have thought of the gathering as an exclusive Windows 10 occasion, the company sure knew how to surprise attendees by bringing the unexpected. From OS features to device extensions, consumers are bound to get a taste of a "Next Chapter" uniquely offered by the tech giant.

To begin with, Microsoft has generously announced that the Windows 10, earlier thought of as the Windows 9 / Windows Threshold, will be offered for free.

As reported by PCWorld, Windows 10 will be a $0-treat for current Windows 7 and Windows 8 users, provided that they upgrade within one year following the operating system's launch. The outlet went on to indicate that users will receive updates so long as the switch is made.

At present, Windows upgrade licenses start from $119.99, Ars Technica wrote. According to the report, the reason behind Microsoft's noble move is to "unify" the Windows ecosystem.

Aside from the kick-starting free upgrade, Microsoft also dropped its entry on augmented reality (AR) -- the HoloLens. As told by Engadget, the HoloLens is a wireless, wearable computer that enables Windows Holographic. Basically, the system will allow users to visualize 3D projections, providing connection between the physical and digital realms.

To make the news even better, the Windows Holographic system isn't just designed for gaming, but its applications are set to run across an array of Windows devices. Users can make their own Holograms through an app called the HoloStudio.

Earlier, Microsoft has indicated its desire to address enterprise, and it looks like the company's going to do the job on a large scale. Meet the Surface Hub, an 84-inch, 4K touch-enabled screen that practically functions as the world's largest tablet.

In another report, PCWorld specified that the hardware is designed for office collaboration, but it also appears to provide more than such. The gargantuan display is said to pack a camera, microphone, motion sensor, motion sensors and Wi-Fi / Bluetooth support.

As told by the outlet, the Surface Hub is also capable of supporting video conferences, whiteboard sessions and connectivity features. That said, the monstrous device may be connected to smaller hardwares such as phones, PCs and tablets.

The event didn't pass without the mention of Xbox One. Microsoft's Terry Myerson announced that universal Windows apps will be working for the console, CNET reported. In addition, an Xbox app for the Windows 10 is expected to arrive. How these systems are going to operate wasn't told in full detail, but we'll surely be on the lookout for more information.

Other notable features mentioned in the event are personal digital assistant Cortana and new browser "Project Spartan."

Watch the event's highlights (via The Verge) below.