Microsoft has released a huge, free update to last year's Windows 8 operating system.

Windows 8.1 might sound like a minor upgrade, but the revamped OS has won rave reviews from the tech press who said it addressed many of the original software's flaws.

The update is available through a free download to anyone running a current copy of Windows 8 for desktops, laptops and Windows RT tablets.

If you have a machine running Windows 7, or want to upgrade to Windows 8.1, charges will apply however.

The major new features of the OS include:

  • The 'Start' button returns - though not quite as you remember. Tap the new icon located in the lower-left of the screen, and it will take you back to the Tile homescreen. Right click the button to access tools including the control panel, and shutdown/restart options
  • You can not boot straight to the traditional desktop, instead of the tiled homescreen. The option is hiding in the new Taskbar and Navigation properties menu, which you can find by right-clicking the taskbar
  • Homescreen tile sizes - you can now set the tiles to be one of four different sizes - leading to an experience more akin to that on Windows Phone
  • Universal search - instead of searching within apps you can now search from anywhere - for anything
  • Better multitasking, with options to run four apps side-by-side from the tile screen
  • Better cloud integration with SkyDrive
  • Redesigned Windows Store making it easier to find new and better apps
  • Automatic app updates - a feature you can find in the Windows Store settings
  • Hot Corners can be disabled, meaning you won't launch unwanted features by accident
  • Reading List, a new app that collects content from Internet Explorer and other apps to read later

Microsoft said of the update:

"Windows 8.1 evolves the Windows vision for highly personalised computing while showcasing Microsoft’s continued commitment to rapid and responsive development. It marks a wave of new, innovative devices coming for consumers and businesses — from the convenience and mobility of tablets and 2-in-1s to the productive experience expected from laptops, all-in-ones and specialised industry devices."

The reviews so far have been positive. The Verge gave the OS 8.8/10, and said that it was "a mostly successful attempt to make the platform more usable for tablets and PCs alike". While the site said Microsoft still had "more to do" it said the update made the OS "something easier and more familiar".

Meanwhile Cnet said the OS was not a "radical departure" but was instead "a series of generally positive tweaks and updates to Microsoft's forward-thinking OS, and a clear attempt to change the tenor of the conversation about Windows 8".

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