Here's a look back on some major milestones from those 30 years.
1985: Windows 1.0
By modern standards, the first release of Windows was rudimentary. It was also late, arriving in the marketplace about a year and a half after it had originally been supposed to ship. Still, it planted a flag in the computing landscape that would endure for at least three decades and would eventually run on billions of PCs. Most importantly, it cemented Microsoft's reputation for long-term support of its software. Windows 1.0 was officially supported for more than 16 years; it didn't make the list of obsolete products until December 31, 2001.
1988: Windows/386 (version 2.1)
Sorry, but your puny 80286-based PC wasn't good enough for Windows/386, which was the first Windows version to support a protected-mode kernel and actual multitasking. A separate, single-tasking Windows/286 (also version 2.1) was available as well. DOS diehards weren't impressed, preferring competitors like Quarterdeck's DesqView, which had been released before Windows 1.0 and allowed MS-DOS programs to run simultaneously in overlapping windows.
1993: Windows 3.11 (Windows for Workgroups)
Somewhere in my garage, at the bottom of a dusty box filled with old PC parts, I am pretty certain I still have the original screwdriver that came with Windows for Workgroups 3.11. That tool was included to help buyers install the network card, also included in the package, highlighting the signature feature of this version. The tiny numbering increment to this version belies its changes, which included support for 32-bit disk and file access and (drumroll, please) 32-bit networking support. It was the first version to support TCP/IP networking, just in time for the dawn of the commercial Internet.
1996: Windows 95 OEM SR2
Yes, yes, it was the original Windows 95, released in August 1995, that got the Rolling Stones theme song ("Start me up") and a party hosted by Jay Leno. That was one helluva marketing budget. But it wasn't until a year later that OEMs got their hands on this update, which was the first Windows version to support FAT32. That was a huge upgrade in terms of performance, storage efficiency, and reliability.
1996: Windows NT 4.0
Microsoft had been developing parallel versions of Windows for businesses and consumers for several years, starting in the early 1990s. Dave Cutler, father of the Windows NT line, called the DOS-based Windows family a "toy operating system." NT was the only choice for serious businesses, and version 4.0 was noteworthy because it was the first to add the Windows 95 shell (complete with Start menu) to the robust NT architecture. The bad news? It required massive amounts of RAM: 32 MB (that's megabytes, with an M) just to run normal desktop programs!
1999: Windows 98 Second Edition
Before there were service packs, there were second editions. The first release of Windows 98 was known mostly for the infamous demo in which Bill Gates caused a Blue Screen of Death simply by plugging in a USB device. The Second Edition arrived less than a year after the original release, with its own retail packaging, and was followed by the disastrous Windows Me less than a year later. They were the last gasp of the old DOS-based Windows versions.
In the new millennium, Microsoft was plagued by security issues. The original release of Windows XP in 2001 was a very big deal, unifying the consumer and Windows versions. After that launch, the company focused on security, re-engineering its development process. Windows XP Service Pack 2, code-named "Springboard," was one of the first products to come out of that initiative. This should have been a separate Windows release, but Microsoft made the decision to release it as a free service pack to get its significant improvements on as many desktops as possible, as quickly as possible.
2006: Windows Vista
Through the years, Vista has become the punch line for a thousand jokes, and it was a critical if not commercial flop. Its signature architectural feature, User Account Control, was derided as a usability mess, although it succeeded in convincing software developers to finally release code that didn't require administrative rights. It was buggy and poorly supported by hardware OEMs for the first year. Vista's biggest accomplishment was that it laid the groundwork for what was to become the best-selling version ever.
2009: Windows 7
If Microsoft Windows had a high-water mark, this is it. Windows 7 was basically Vista Second Edition, cleaning up the compatibility and driver problems that had plagued its predecessor. One of its key design goals, in fact, was that any driver or app written for Windows Vista would work perfectly on Windows 7. Under the new leadership of Steven Sinofsky, the Windows team succeeded beyond their wildest dreams. Today, more than six years after its release, Windows 7 is still running on hundreds of millions of PCs.
2015: Windows 10
Windows 8 was a wild gamble on the future of computing. In the process, the radical Windows 8 interface erased much of what had made Windows 7's desktop interface so popular. Windows 10 is an attempt, largely successful, to salvage the best parts of the Windows 8 user experience while restoring the touchstones of Windows 7. It's also likely to be the last "big bang" release of Windows. Going forward, Microsoft has committed to developing "Windows as a service," with new features appearing as automatic updates rather than shrink-wrapped boxes.
The PC is no longer the centerpiece of modern computing, and Windows no longer holds a monopoly on the market for computing devices. Remarkably, though, Windows is still alive and well, 30 years after its tentative debut. Will it last another three decades? Probably not, but it will still be an economic force for many years to come, even if only as a legacy product.
© 2015 CBS Interactive. All rights reserved.