One of the cornerstones of Microsoft’s business has been Office.  Office, along with Windows, has been so successful that its profits have been able to fund a number of less-than-profitable business units over the years and allowed Microsoft to not only survive debacles like the XBox Red Ring of Death but still make a profit while writing off billions in expenses.

Although Microsoft has been pushing Office to a subscription-based service with very affordable non-commercial tiers, I was shocked to see this article from The Verge when I opened up Twitter this morning.

Starting today, you won’t need to have an Office 365 account in order to edit or save documents on IOS or Android devices.  Windows and Mac users don’t get a free version, and they will still need to pony up for an Office 365 subscription to use Office on their PCs.

Although Microsoft has given away products in the past such as the Visual Studio Express Editions and SQL Server Express, I can’t recall a time when they’ve given away one of their core products in a form that wasn’t tied to another revenue generating platform.

OK…that sentence was a little awkward.  What I mean is that while Visual Studio Express and SQL Express are feature limited versions of Microsoft products, they’re still tied to the Windows ecosystem. 

The difference here is that Microsoft is giving away a version of Office, albeit a feature limited one, on platforms that they don’t derive any direct revenue from.

This isn’t an entirely altruistic move – it’s one to ensure that Office remains the dominant productivity platform in the face of multiple mobile options.  It doesn’t really undercut any of their competitors like building Internet Explorer into Windows did to Netscape – Google and Apple already offer free mobile productivity suites as well, and users will have their choice of which suite they want to install and use.

So is this big?  Yes.  Is it shocking?  In some ways, yes.  But its also a move that Microsoft had to make in order to keep Office relevant in an era of open document standards and free alternatives on mobile devices.