Every so often, proponents of open source circulate various high-profile Linux-adoption stories to demonstrate the OS's success over Windows. But these stories often obscure one crucial fact: Such adoptions usually replace proprietary and expensive versions of UNIX, not Windows. Consider two recent cases: Amazon.com and Intel.

Amazon.com reported that adopting Linux cut its technology costs by nearly 25 percent during second quarter 2001—a key benefit given the economic climate and Amazon.com's historic inability to make money. "The decline in absolute dollars spent primarily reflects our migration to a Linux-based technology platform that utilizes a less-costly technology infrastructure, as well as general price reductions for data and telecommunications services due to market overcapacity," the company stated in a filing with the Securities and Exchange Commission (SEC). Technology news agencies seized on these comments as a huge win for Linux and a huge potential loss for Windows. However, what the agencies didn't point out is that Amazon.com replaced proprietary UNIX servers, which the company used for its back-end services.

Intel hit the anti-Microsoft press's radar when Vice President and Director of Information Technology Doug Busch commented that the company had saved millions of dollars by implementing an intranet application that lets users inexpensively share streaming-video feeds across corporate locations. Busch said the peer-to-peer software runs on small Intel-based Linux servers and saved the company $200 million in 2001. But as with Amazon.com, Intel's previous solution ran on massive and expensive non-Intel UNIX servers. When asked whether the company would ever consider replacing its Windows machines with Linux, Busch said absolutely not, noting the lack of "robust office packages" available on the Linux platform. Busch threw another wrench into any mass Linux migration scenarios when he noted that the overall cost of Linux and Windows 2000 is almost identical after you factor in support and maintenance.

Another point that Linux-adoption stories often fail to mention is the cost of making the transition from Windows to Linux. This cost is the reason that so few companies undertake such a migration. Converting from UNIX to Linux is relatively straightforward; you can easily recompile most versions of UNIX software to run under Linux. But because Windows is based on entirely different technology, moving from Windows to Linux isn't so simple.

Linux might have the technical credentials to be successful in certain market segments (e.g., Web serving, academia), but the OS will have a hard time overtaking Windows anytime soon. According to International Data Corporation (IDC), Linux currently owns 24 percent of the server market, whereas Windows owns about 38 percent. (On the desktop, Linux's market share is too small to be measured, whereas Windows owns about 88 percent of the market.) Linux will continue in the number-two position at least through 2005, according to IDC. But most of Linux's market-share gains during the past few years have been at the expense of proprietary UNIX solutions—not Windows.