At its launch, on November 20, 1985, only a handful of tech enthusiasts thought that Microsoft's new Windows 1.0, and CEO and chairman Bill Gates' vision of a graphical user interface would change the world.
After all, Apple had introduced its breakthrough Macintosh a year earlier. With its "1984" Superbowl ad, Apple positioned the Mac as the platform for creative minds, while the Microsoft-powered (NASDAQ: MSFT) IBM-compatible PC was seen as designed for geeky bean counters in corporate cubicles.
Twenty-five years later, Gates is retired except for his role as chairman of the board, and Windows appears to be riding higher than ever. Still, much of that earlier image still hangs over the company.
The computing industry continues to morph at a dizzying rate and Microsoft is once again up against tough challenges, including emerging sectors like cloud computing and smartphones, that could be the software goliath's undoing in the next 25 years. On the plus side, in its first full year on the market, Windows 7 is the fastest-selling version ever with more than 240 million licenses sold.
However, back in 1985, Microsoft was known as the company that made MS-DOS -- a decidedly ungraphical operating system. Windows 1 was an add-on to DOS meant to give it some of the ease of use of the Mac -- a move that eventually led to the demise of Microsoft's relationships with both Apple and IBM.
Microsoft eventually won the lawsuit that Apple had filed against it claiming theft of Apple's intellectual property in regard to some Windows' features.
It also eventually saw IBM leave the market for PCs altogether, but not until after years of battling back and forth with Big Blue, which felt that it had been sucker-punched by the emergence of Windows versus OS/2. Many observers felt OS/2 was a more capable operating system and it had its own graphical user interface (GUI) called Presentation Manager.
The irony was that Microsoft was codeveloping OS/2 and Presentation Manager with IBM at the same time that it was moving Windows ahead in its priorities.
It wasn't until May 1990, when Microsoft launched Windows 3.0, the first version that actually delivered to consumers and businesses the features they demanded at a lower price than the Mac.
The next 20 years went by in a blur.
In the late 1980s, Microsoft introduced the Office productivity suite when other competitors were still selling individual products (though Office was originally only available on the Mac). Office provided the fuel for Windows' next growth phase, which was to move onto corporate networks and eventually render the then dominant network provider Novell harmless.
At the same time, Microsoft started to shoot for a larger share of the business computing pie. In 1993 it shipped Windows NT 3.1, its first attempt at an "industrial-strength" server and network operating system, which also suffered slow initial acceptance.
Then came Windows 95, Windows 98, Windows 2000, and Windows XP -- the latter being the most popular version of Windows in its history until Windows 7. In the process, Windows evolved from a 16-bit OS to 32-bits and, now, to 64-bits -- and Windows NT and Windows merged much of their code base.
While Windows Vista, which came along in 2007, wasn't exactly a failure, it never took off with business customers, until it was reworked into Windows 7, which launched on Oct. 22, 2009. Microsoft has said it is already at work on the next major update, currently referred to as "Windows 8."
High on the list of new features coming in Windows 8 is an "instant on" capability so that users won't have to wait for their computers to start up. It is also expected to provide much tighter links to Microsoft's evolving cloud computing platforms. Rumors and leaks have Windows 8's availability slated for sometime in 2012.