If there's one thing to be taken away from Microsoft BUILD it is that Windows 10 is not the operating system any of us were expecting.
Microsoft's rigid development structure has gone, in its place a new operating system that can power one of the most innovative gadgets we've seen in years (HoloLens) and yet at the same time, power smartphones, tablets and desktops.
This isn't Microsoft having a spring clean, it's a bulldozer, and as you'll discover, it's for the best.
Microsoft's astonishing HoloLens seems like the sensible place to start. When HoloLens was first unveiled it pretty much broadsided much of the press (us included) and has continued to do so each time it has been shown.
The augmented-reality headset quite literally sandwiches your digital world and the real world together. Skype calls now appear in thin air while weather forecasts magically appear on your desk.
The headset is Google Glass on nitro - turning real-life into a fully interactive operating system.
BUILD added to this by revealing just some of the companies that have already started working with the technology.
Next up is the operating system that'll power HoloLens: Windows 10. Microsoft's new operating system is integral to every single device they now make - it's inside the Xbox One, it's going to power the new range of Surface tablets and it's going to turn Microsoft's Lumia smartphones into portable computers.
All of this is underpinned by 'Continuum', a feature which means that everything on Windows 10 is synced and adaptive.
While it's just one word, 'Continuum' covers a broad range of features. This includes the ability to plug your Windows 10 smartphone into a display and have it become a fully-functioning desktop.
It also means there will eventually be one Windows Store, that'll work across all devices. You'll download the app once and it'll work on desktop, smartphone and HoloLens.
Finally Microsoft has been tinkering with the way developers create apps, adding a range of SDKs that promise to make it easier for developers to create apps based on existing iOS or Android apps.
Internet Explorer is dead, in its place is Microsoft Edge. Originally known by the Halo-inspired name 'Project Spartan', Edge is the next-generation browser that Microsoft believes will stop you downloading Firefox or Chrome the moment you buy a new laptop.
Featuring full integration with all of Windows 10's new features, Edge has Cortana built-in and offers on-screen dictation, offline-reading and more.
Of course the biggest shock to many will be the design. Edge looks drastically different to anything before it, with minimalist icons, a fresh clean layout and the promise of serious speed.