Twelve months after launching the heavily-criticized Windows 8, Microsoft has begun rolling out the operating system’s eagerly awaited update, officially known as Windows 8.1.

As of 04:00 PST today, Windows 8.1 will be made available to download on the Windows Store, available for free for all existing Windows 8 users. The update brings a wealth of new features that Microsoft hopes will silence the chorus of critics that have repeatedly derided its OS, together with the usual performance upgrades. Windows 8.1 will also be available to buy in retail stores, and pre-loaded onto new computers from tomorrow.

So what does Windows 8.1 mean? Well, if you’re one of those who’s been wary of upgrading to the touch-centric operating system, you might finally be convinced that it’s worth doing so. No doubt about it, Windows 8 faced plenty of criticism when it was rolled out last year. People hated the fact that Microsoft took away their Start Menu, swapping it out for a Windows Phone-like Start Screen packed with dozens of tiles and no ‘easy’ way to find your files or access the Control Panel. The Start Screen was all about promoting Microsoft’s new app ecosystem, and while Windows 8 PCs can do everything that a Windows 7 PC can do, it was all very different, and confusing.

But things might chance now that Windows 8.1 has arrived. For one thing, people are slowly coming around to Windows 8’s changes, and with the update Microsoft has fixed some of the biggest problems that people had with it. Just like most major updates to technology, it can take a while to iron out the bugs and that’s what Microsoft’s spent the last year doing.

As for the new features, one of the most noticeable changes is that users now have more control over the Start Screen. Microsoft is sticking to its guns over its Metro-style interface, but at least those fiddly Live Tiles are now more customizable with a choice of sizes available. A second big change is that users can now open multiple apps on screen at once – previously it was only possible to open two side-by-side using the ‘snap’ mode, but now its possible to display up to four apps at once. And of course, the Start Button has finally returned with Windows 8.1, although as we saw previously on SiliconANGLE, it’s still not exactly how we remember it. As for search, Bing has been more heavily integrated across the OS, allowing users to search both the web and their own files from a single interface.

There are plenty of other changes to look forward too. Some of the important ones include a Mail app that’s been given an overhaul, updates to Skype and Internet Explorer 11, and native 3D printer support for the first time on any major OS.

The Windows 8.1 download is available for free in the Windows Store for all current Windows 8 users. Those who’re still using Windows 7 or older will need to buy and install the original Windows 8 (currently $119, or $199 for the Windows 8 Pro version) before they can make the upgrade.

If you’re still wondering whether or not Windows 8 is worth the trouble, you might want to tune into Microsoft’s IamA session on Reddit from 10:30 to 12:00 PST, where its engineers will attempt to answer your questions about the new update.