Operating Systems tend to generate emotional or religious feeling, and proponents cite the technical superiority of their Chosen One—but most businesses care about the bottom line. We evaluated Linux, Windows and Mac systems purely for their ROI: How much does it cost to install, support, maintain and feed each one? What's the return on the investment? For fairness, there are two articles for each OS—a "reasons to" and a "reasons not to," both of which focus only on the numbers.

Eight Financial Reasons Why You Should Use Mac OS
Mac OS is the hands-down operating system winner, from the perspective of cost effectiveness. Sparser help desk calls, stronger security and cheaper licensing are three big reasons why. But there are eight of 'em, all told.

Seven Reasons to Think Twice About Macs in the Enterprise
Apple commercials show the ultra-cool Mac mocking the pinstriped PC. Macs, it seems, don't care to be businesslike—they'd rather be up late mixing video. And there are other, more pragmatic reasons to keep them out of the enterprise—reasons that a penny-pinching CFO would understand.

Seven Financial Reasons to Use Linux in the Enterprise
Even if the total cost of ownership were equal to that of a proprietary system, Linux might still carry a financial incentive—find out why.

Eight Reasons NOT to Use Linux in the Enterprise
When considering licensing costs, support, management tools, support and training, Windows and even Solaris make better financial sense than using Linux.

Five Business Reasons for Adopting the Windows Platform
Microsoft Windows not only works; it is simple to set up, maintain and keep users working—which fuels profits.

Seven Financial Reasons Not to Use Windows
It's not that you shouldn't use Windows, it just that it's not always the most economical choice for your company. Here are seven surefire reasons to consider Linux, Unix or Mac alternatives.