The list includes six editions: Windows 10 Home, Pro, Enterprise, Education, Mobile and Mobile Enterprise. That's one more than 2012's Windows 8, which included the now-defunct Windows RT, and the same number of SKUs as 2009's Windows 7 offered for PCs alone.
"No matter which Windows 10 device our customers use, the experience will feel comfortable, and there will be a single, universal Windows Store where they can find, try and buy Universal Windows apps," Tony Prophet, the former HP executive who now leads Windows marketing, said on a company blog post yesterday, touting one of the primary messages Microsoft has used to bang the drum.
Microsoft's SKU list is divided into two groups. The first, dedicated to PCs, 2-and-1s and tablets 8-in. or larger, includes Home, Pro, Enterprise and Education. The second -- Mobile and Mobile Enterprise -- applies to smartphones and sub-8-in. tablets.
Windows 10 Home, Windows 10 Pro and Windows 10 Enterprise will be the new counterparts to the same-named editions of Windows 8.1. Meanwhile, Mobile and Mobile Enterprise will replace or augment what was formerly the Windows Phone operating system.
Microsoft did not reveal the retail pricing of the SKUs. Although it typically does that closer to the actual launch date, some prices disclosed for past Windows may be initially moot as the company will offer free upgrades from Window 7 and 8.1 to Home or Pro for a year after release.
Windows 10 Home will be the classic consumer edition pre-loaded on new PCs, hybrids like Microsoft's own Surface and larger x86-based tablets.
Windows 10 Pro, pitched by Prophet at small businesses, will add to core of Home with business-specific features like domain joining -- critical for connecting to a company's network -- and will cost more than Home. Business-class computers and other devices will come pre-loaded with Pro.
Windows 10 Enterprise will be available only to customers through volume licensing deals. Businesses with the Software Assurance annuity program will be able to upgrade to Windows 10 Enterprise free of charge.
Microsoft also confirmed what it had strongly hinted at earlier, and what analysts had assumed for months: Only Windows 10 Enterprise will allow customers to lock down devices with the Long-term servicing branch (LTS) update and upgrade track. Machines on LTS will receive only security patches and other critical fixes, and will be spared the feature, functionality and user interface (UI) changes Microsoft plans to deliver on an accelerated tempo.
Windows 10 Education is a new SKU and, like Enterprise, will be available only to volume licensing customers, in this case schools. Microsoft did not elaborate on the differences between Education and Enterprise, but said, "There will be paths for schools and students using Windows 10 Home and Windows 10 Pro devices to upgrade to Windows 10 Education."
It's likely, then, that Microsoft will let students at schools licensed for Education upgrade free of charge to the SKU from both a new Windows 10 device and from older PCs that had previously been upgraded free of charge from Windows 7 and 8.1.
Windows 10 Mobile and Windows 10 Mobile Enterprise for smartphones and smaller tablets will have the same core features, but will be differentiated in at least one way: The latter, available only to volume licensing customers, will have "flexible ways for businesses to manage updates," according to Prophet, who did not expand on that.
He may have been talking about the same LTS track that Windows 10 Enterprise on desktops will offer, or referring to support for the new Windows Update for Business (WUB) service, or both.
Windows 10 Pro and Enterprise are the two SKUs now known to also support WUB, which will let businesses manage the update and upgrade cadence by, at least, putting systems into various "rings," or speed tracks. The Redmond, Wash. firm has not said whether Enterprise or Enterprise Mobile will also support more than LTS, although analysts assume so. Nor has Microsoft made it clear whether Mobile Enterprise will connect to WUB.
Prophet continued to use the general "this summer" to describe the Windows 10 release timetable. "We are making strong progress with Windows 10, and we are on track to make it available this summer," he said.