The latest version of Microsoft's OS - Windows 10 - has been designed to run across PC, tablet, mobile and even the Xbox One games console. It brings with it a host of new features, some of which have been seen on other systems - but with the tech corporation implementing its own tweaks.
Free upgrade
Microsoft will be making Windows 10 available as a free upgrade for all Windows 7, 8.1 and Windows Phone 8.1 users - for the first year of Windows 10's life, at least. After that, you're going to have to pay - although Microsoft is yet to reveal how much it will cost.
Windows 10 for mobile
Microsoft will be dropping the "Windows Phone" moniker for its mobile platform. Instead, it will be called Windows 10 - due to the fact the mobile experience is just a continuation of the tablet and PC.
It will still look familiar to current users because the Live Tiles are staying put. But now you'll be able to put a wallpaper behind them and, in doing so, make the tiles translucent instead of them remaining solid blocks. It'll let you give your phone a truly personal touch.
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Microsoft's core apps - including Word; Excel and Powerpoint - will work seamlessly across all platforms. For users, this means they'll function much in the same way across all devices. That means features on tablet and PC such as inputting transition slides in Powerpoint can also be done on mobile. The only real difference will be the way they reformat to fit the screen.
The Outlook mail app has been given a revamp too. Word has been integrated into the app in order to make composing messages a lot easier, while you'll now be able to use swipe gestures to delete and archive messages.
Action Center (Microsoft's notification centre) has received some tweaks too. Individual notifications can now be dismissed and, because it syncs with other devices, deleting a message notification, for example, will delete it from your tablet too. Further action settings can accessed by a simple pull down too.
Microsoft has been keen to push its voice recognition software; with Windows 10 for mobile, it's no different. Microsoft has made it more intelligent and put more focus on it; a mic button now appears wherever you can type. It'll be able to understand most, if not all, of the names stored in your phonebook and even hashtags. It looks like tweeting just got a lot more interesting.
When you receive a text message, a notification will pop up. You'll now be able to respond from this notification rather go into the messaging app. And because Microsoft owns Skype, you can switch between SMS and Skype messaging for the same contact - much like you can with Google's Hangouts.
Elsewhere, the iconic Internet Explorer browser is about to make way for a new product - currently codenamed Project Spartan. This new internet browser will have a host of new features, including the ability to draw and annotate on the screen. And the default camera for all Windows 10 devices will be the recently released Lumia Camera app.
Nokia Lumia phones are among the first to benefit from the app, which will also be passed on to other Windows 10 phones with its features including automatic HDR and 4K recording.
Another addition to the app line-up is Nokia HERE Maps, which will power the new Microsoft Maps app. It'll offer directions based on the proximity to your destination; if it thinks you can walk there, it'll let you know. You can also ask Cortana to repeat instructions and ask the virtual assistant to remember where you parked.
Windows 10 for PC and tablet
Windows 10 aims to bring together the best bits of both Windows 7 and 8.1, as well as elements of its mobile software into one solid performing desktop OS.
Cortana is coming over from Microsoft's smartphones and it'll feature prominently on desktop. There's a dedicated input box where you can type or speak queries, with Cortana producing results from the web, your files and even apps - whether they be ones you own or ones from the store. You'll even be able to dictate text, for example, for emails and ask her to send it. And like the obedient person that Cortana "is", it'll oblige.
You can also use Cortana to help you find content relating to a particular theme. Microsoft showcased this at its press conference, asking it to show all photos taken in December. It managed to deliver results within seconds. It'll also be able to search any connected personal or professional OneDrive cloud storage libraries.
The tiles that featured heavily in Windows 8 are still there, but are now less prominent. You'll now be given what is considered to be a 'classic' looking Windows start screen, along with the tiles. It looks a lot less in-your-face than before. If you liked the tiles approach, however, you'll have the option of expanding them to fill your screen.
Microsoft's new Project Spartan browser will replace Internet Explorer on the desktop as it will and mobile; that means it'll bring a much more minimalist look where the content is king. A reading mode will remove adverts, leaving you with just text and pictures, while you'll also be able to make notes on pages and send copies to friends.
The corporation has also implemented a new feature labelled Continuum. It works best on two-in-one devices such as Surface Pro tablets that comprise a tablet and detachable keyboard. If the keyboard is attached, it'll function and perform like a laptop, albeit with moveable windows. But, remove the keyboard and press a prompt button, and the pages will fill the screen to make working a lot easier.
The whole user experience has been made a lot easier too. Settings have all been placed in one menu and are easier to navigate.
Windows 10 Xbox integration
The new Windows 10 OS will now feature an Xbox app that will let you view your progress and achievements in games, as well as chat to your friends.
But the most significant news is that you'll be able to stream Xbox games to a Windows 10 PC or tablet in your home, provided those devices are on the same network. Microsoft plans to let users play online with each across platforms, and it'll be making some Xbox games available for PC.
Surface Hub
In addition to its new software, Microsoft unveiled its latest hardware at the launch. The first of the new products is the Surface Hub 4K screen, which is essentially an incredibly large tablet - targeted at businesses and designed to be used in meeting situations.
It can support several touch inputs at once, letting more than one person draw on the screen at the same time. It can also be used for video conferencing thanks to built-in Kinect cameras and microphones. Users will be able to Skype others and draw on the screen, the person the other end will be able to see the annotations being made.
It'll be able to run any Windows app and can sync with Windows 10 tablets, PCs and smartphones. This means you can take the meeting's work away with you, if you wanted to that is. Meanwhile, it'll work with iOS devices as well - but that functionality will be limited to Microsoft apps such as Word and Powerpoint.
The Surface Hub will be available in 55in and 84in variants. Pricing details have yet to be confirmed.
HoloLens
Last, but certainly not least given it was perhaps the biggest surprise for all, was the announcement of the HoloLens headset. Unlike Google Glass and the Oculus Rift Virtual Reality headsets that use screens to project images, the HoloLens relies on holographic technology.
It'll beam high-definition images into your world with some examples being a TV or a game that fills your room. It responds to gestures, voice commands and even eye movements, while also boasting spatial audio to create the effect of sounds behind you.
Microsoft hasn't said when the HoloLens will become available to purchase for yourself, but we have been told to expect it during Windows 10's lifespan.