On Thursday, October 17, 2013 and Friday, October 18, 2013, Microsoft will unleash Windows 8.1, its next Windows release for PCs and tablets. Here's what you need to know to get ready for Windows 8.1, regardless of which version of Windows you're currently running.

Obtaining Windows 8.1

How you get from your current version of Windows to Windows 8.1 will vary depending on which version you're using. If it's Windows XP, Vista, or 7, bad news: You need to purchase the full retail version of the product (which costs $119.99 for Windows 8.1 "Core" and $199.99 for Windows 8.1 Pro) starting on October 18. And if you upgrade using this product, you'll have to reinstall all of your applications.

There is one workaround, at least for Windows 7 users: Buy a retail version of the Windows 8 (as in 8.0) upgrade instead (same pricing as noted above) and upgrade to that instead. Then you can get Windows 8.1 for free, and you won't have lost any applications in the process.

Windows 8 users, as noted above, can upgrade to Windows 8.1 for free. But you won't be using (and thus paying for) a retail product. Instead, you'll be able to download the updater from the Windows Store and upgrade electronically. This starts at 4 am PT/7 am ET on October 17. I'll have a complete walkthrough of this process on October 18.

If you previously upgraded from Windows 8 to the Windows 8.1 Preview, bad news: You can upgrade to the final version of Windows 8.1 for free, of course. But you will have to reinstall all of your desktop applications and Metro-style apps (the ones that don't ship as part of Windows). Otherwise, this upgrade will work the same as updating from the original version of Windows 8.

Mac user? Assuming you don't already have Windows 8 running in Boot Camp or in a virtual environment, you will need to purchase one of the retail versions of the product mentioned above. This is true for anyone that wishes to install Windows 8.1 in a virtual machine, of course, including those using Hyper-V, VMWare Workstation, or whatever.

Learn more about Windows 8.1

If you're curious about Windows 8.1, you won't be surprised to discover I've written a lot about this release and plan to write a lot more in the near future. Here's a rundown of the most important stuff you should be reading:

Windows 8.1 Review

I'm now using the final shipping version of Windows 8.1 exclusively on all of my PCs. And despite worries that Microsoft would need to fix issues between this product's release to manufacturing (RTM) and general availability (GA) in October, I can report that the firm has delivered a solid, meaningful update to Windows 8. It won't answer all of the complaints, but Windows 8.1 is a big improvement for both desktop PC and mobile device users.

Hands-On with Windows 8.1

The ultimate guide to what’s new in the Windows 8.1 update for Windows 8 and RT, this article serves as the front-end for other articles that highlight my hands-on time using the new and updated features in Windows 8.1, and it will grow over time as new articles are added.

Windows 8.1 Tips

With Windows 8.1 heading out to millions of users, I've collected the tips I've already written for Microsoft's latest OS version and will be adding to it regularly going forward. Here's a single place where can go to find what you need and master Windows 8.1.

Windows 8.1 Book

Rafael Rivera and I are writing a full-length e-book about Windows 8.1 under the code-name Windows 8.1 Book. (Final name to be determined.) As with my previous book, Paul Thurrott's Windows Phone 8, this book will be written transparently and publicly, and you can follow along, download chapter and book updates, and provide feedback as it's written. Unlike that previous book, however, Windows 8.1 Book won't be free. But it will be very inexpensive: Using the pricing model popularized by mobile apps, the suggested price will be just $2, though we'll let you pick your own price if you'd prefer to pay more (or less). With that purchase, you will get regular ongoing updates to the book, authors who will personally respond to and address your concerns and feedback, and your choice of e-book formats (PDF, MOBI, EPUB and so on). When Windows 8.1 Book reaches the 1.0 milestone, we'll deliver it on Amazon Kindle and Barnes & Noble Nook as well, though those e-book sellers will require their own payment. (Don't worry, it will still be very low-cost.)

We'll have a dedicated site available for the book soon, which will facilitate payments and ongoing updates to the book as it is written. But if you follow this site, you know we've been working on this book for the past month and that I've already posted several updates. Here are the first available chapters.

Windows 8.1 Book: Music 0.1

Here's a first look at the next chapter in progress for Windows 8.1 Book: Music. This chapter discusses the Xbox Music app, and will be used as the basis for the next update to Paul Thurrott's Xbox Music as well...

Windows 8.1 Book: First Draft of the Video Chapter is Now Complete

The first draft of the Video chapter for Windows 8.1 Book is now complete. This chapter focuses on the Xbox Video app, as you might expect, but also discusses how SmartGlass can be used with purchased content and an Xbox 360...

Windows 8.1 Book: First Draft of the Calendar Chapter is Now Complete

The first draft of the Calendar chapter for Windows 8.1 Book is now complete. This chapter focuses on the Calendar app, as you might expect. But with this second first draft chapter, I'm also issuing the first and very incomplete version of the full book document...

Windows 8.1 Book: First Draft of the Photos Chapter is Now Complete

The first draft of the Photos chapter for Windows 8.1 Book is now complete. This chapter focuses on the primary photo experiences in Windows 8.1, which are available through the Photos and Camera apps...

As you might expect, there's more coming. See you soon.