There are seven different versions of -- that's right, seven.
That's a pretty intimidating number of options, until you take into account that only three of those versions -- Windows 10 Home, Windows 10 Pro, and Windows 10 Mobile -- are available to normal consumers. The other four, Windows 10 Enterprise, Windows 10 Mobile Enterprise, Windows 10 Education, and Windows 10 IoT Core, are available only to volume licensing clients, schools, and intrepid startups.
Still, three different consumer-oriented versions of Microsoft's latest operating system means you'll need to make a choice. Here are your options:
Windows 10 Home
For most people, Windows 10 Home will be the version of choice. It's also the version you'll get if you take Microsoft's free upgrade path and you're currently running Windows 7 Starter, Windows 7 Home Basic, Windows 7 Home Premium, or Windows 8.1.
Here's a handy upgrade chart to help you sort things out:
Windows 10 Home gets you all the fancy new Windows 10 features you've been hearing about, including Microsoft's voice-activated search buddy Cortana, the speedy new stripped-down browser Edge, and a few much-needed improvements such as virtual desktops and the return of the Start menu. You'll also be able to take advantage of Xbox One integration and "Continuum," a Windows 10 feature that allows you to switch seamlessly between different devices (e.g. from a phone to a PC) without compromising your experience. Windows 10 Home is designed for desktops, laptops, and 2-in-1 computers such as the Microsoft Surface, so the interface is intuitive across both touch and non-touch platforms, and switches based on how you're using your device.
What Windows 10 Home won't have access to is Windows Update for Business, an advanced version of Windows Update that allows business users to more effectively manage and secure multiple devices. Most average users won't need this extra layer of security and control, because most average users are not managing a fleet of devices.
Windows 10 Pro
Small businesses with a "bring your own device" policy will want to look into Windows 10 Pro, which includes all of the same new features found in Windows 10 Home (right down to the Xbox One integration -- "professional" doesn't mean "no gaming"), as well as a few extra tools to ensure that sensitive data is kept secure. Designed for desktops, laptops, and 2-in-1 computers, Windows 10 Pro is the version you'll receive if you take Microsoft's free upgrade and you're currently running Windows 7 Professional, Windows 7 Ultimate, or Windows 8.1 Pro.
Windows 10 Pro features extra security and control options, including domain join services, BitLocker drive encryption, remote access services, and a group policy editor -- tools that will help you make sure the devices in your network are secure and up-to-date. This version will also have access to the aforementioned Windows Update for Business, which allows you to manage, update, and secure multiple devices from one place.
While Windows 10 Pro offers "extra" security options, that doesn't mean Windows 10 Home is less secure -- so don't run out and buy this more expensive version of Windows 10 simply because you want to protect your PC. Windows 10 Pro's additional security options mostly deal with the insecurity of having multiple devices on one network, including employee-owned devices, which are inherently less secure.
Windows 10 Mobile
If you have a Windows Phone, it's now a phone that runs Windows 10 Mobile -- the version of Windows 10 designed for mobile devices. Microsoft is dropping the "Windows Phone" branding in favor of a "universal" operating system that works on all devices.
Windows 10 Mobile looks like Windows Phone 8.1, but there are some under-the-hood changes. Windows 10 Mobile comes with a free, touch-friendly version of Microsoft Office, works with universal apps that run on a variety of devices (e.g. PCs, tablets, phones), and is part of Microsoft's Continuum -- so you're able to switch between your phone and desktop seamlessly. It's easier now to port iOS and Android apps to the Windows platform, so Windows 10 Mobile users should also see an influx of apps in the next year or so.