On October 5, 1991, the young man who would one day become the world's most famous programmer - and the brand name and poster boy for the open source software movement - sent a message to a newsgroup announcing the birth of what would become the Linux operating system.

You can read that original message that marks the birth of Linux as an open source project, posted by Linus Benedict Torvalds, on Google's archive of a newsgroup called comp.os.minix .

It is hard to guess how many programmers and system administrators have been educated by the Linux development project, but it forms the core of what so many experts and newbies believe in terms of what an operating system should have in it, how that code is created, and how the systems software stack that rides atop of it is created and maintained.

It is safe to say that many millions of IT experts have been affected, either directly or indirectly, by Linux and the open source software movement it unleashed on corporations. While academic and government institutions had long since supported open source software projects as well as the Unix open systems movement, it is Linux - first and foremost - that made open source a commercial idea and one that corporations could embrace.

Linux has come a long way in those intervening 17 years, which are a bit like dog years with respect to how computer technology (both hardware and software) moves at an accelerated pace compared to other technologies and areas of the economy. It is hard to say if Linux is middle-aged or not, since the successors to OS/360 are still around more than four decades later (in actual time), and the original Unix is almost as old.

Even the commercial implementations of Unix are three decades old, and commercial Windows servers became a reality in 1994, more than 14 years ago. Who is to say how long any of these platforms will be around in production environments, but the history of the computer industry suggests that legacy platforms linger longer than many expect but lose their potency in the market ahead of when many might have hoped. In many companies these days, the only two alternatives are Linux and Windows for new applications - and some day, far into the future that is hard to conceive, these will be legacy platforms too.

What Windows Promised to Be

But it's remarkable that an open source movement backed by a handful of commercial entities with very little marketing muscle - at least compared to the established proprietary and Unix operating system providers who made so much money in the 1980s and 1990s - could take on the data center and, more importantly, get the begrudging support of the very system sellers who had the most to lose if Linux took off. This is a testament to the powerful idea of a cross platform, open source operating system. Linux is what Unix should have been and wasn't.

Linux is what Windows had once promised to be - at least in terms of cross-platform support. In the wake of the PowerPC alliance from IBM, Apple, and Motorola in 1991, Microsoft made a commitment to support Windows NT 3.51 on PowerPC chips. Windows eventually added support for Digital's Alpha NEC's and SGI's MIPS chips. Workstation maker Intergraph ported Windows NT 3.51 to its Clipper chips and said it was creating a port to Sparc chips from Sun. Neither ports saw the light of day.

Windows NT 4.0, which came out in 1996, only supported nothing more than f32-bit x86, Alpha, and MIPS chips, and by the turn of the millennium, only x86 chips were supported. (Interestingly, the PowerPC alliance also lined up IBM's OS/2 and AIX Unixes - the OS/2 was never delivered - and even Sun Microsystems' SunOS Unix was slated for the PowerPC chips. IBM also ported its OS/400 minicomputer operating system to the 64-bit variants of PowerPC).

While Microsoft has expanded support to cover Itanium processors - mostly at the urging of Hewlett-Packard, Intel's Itanium development partner and the one with the most to gain from Windows-on-Itanium for its high-end Integrity servers - Microsoft has not made good on the initial cross-platform promises for Windows server. Microsoft has suffered from this, but not as much as Intel has been helped.

The beauty of Linux is this: You can't stop a port to a new architecture, even if you wanted to.