For several years, computers running Microsoft's Windows operating system were the only common option for business customers, but the playing field has leveled recently. Mac and Linux aren't just viable alternatives — they're better choices for certain SMBs. Here are some introductory tips to help you decide how best to equip your employees. 

Windows 

Microsoft Windows is still the standard business computing environment. Because it's the most common operating system, and because collaboration is so important, it remains the best choice for most businesses. This has been slowly changing; Windows Vista was not well-received, and Windows XP is now ancient on the tech timeline. Microsoft just released a greatly improved update to Vista called Windows 7, though, so it's much easier to recommend now.

Microsoft Office's e-mail, spreadsheet, presentation, and word processing applications are essential for today's businesses. The suite is also available on Macs, but the latest version is Windows-only, and Linux users are left in the dust. They can still view and edit files in the Office formats, though.

Except for a handful of Mac-only creativity and media applications, you'll find that most business software is available on Windows. Windows has one big downside: It's the most popular target of worms, viruses, trojans, adware, and other dangers. Skilled system administrators can prevent these problems, but they have to take a big chunk out of users' capabilities to do so. The good news is that Microsoft offers the largest technical support system in the world for businesses, administrators, and developers.

The other benefit: Most workers are already trained in Windows. Linux and Mac use is arguably a special skill that's a bit harder to find. For these reasons, Windows is the best bet for businesses that don't employ many power users who need complete access to system features and tools — that would be the majority of employees at most SMBs. 

Mac 

Apple's Mac computers are powerful tools for creative professionals, but they're not cheap. The hardware and designs are cutting edge, but they're not what you're actually paying for. You're investing one to three thousand dollars per machine to use Apple's sleek and stable Mac OS X operating system, along with the powerful software that is exclusively available for it.

Macs have been popular with creatives and media professionals for years. Now they're just about mandatory. Apple develops content creation and editing software in-house, and its applications — Aperture for photographers, Logic for sound engineers, and Final Cut for video and film editors, among others — have become industry standards. You can't use them on Windows or Linux machines. There are Windows alternatives for those platforms, but they're often unpopular and less usable.

New media workers like web developers, bloggers, podcasters, and social media marketers have flocked to Macs recently, too. Because these users spend much of their time in web applications that work on almost any computer, this is more a preference than a necessity. However, those users will often have more experience with the Mac environment, and some non-vital features exclusive to OS X appeal to them.

A somewhat recent switch to Intel processors has allowed Macs to work well with the rest of the computing world. As a result, most of the practical barriers to going Mac have fallen. If you can afford them, Macs are powerful machines with comparatively few stability or security issues — the best bet for many varieties of power user.

Equip teams of creatives, media pros, and web developers working with non-Microsoft platforms like Flash with Macs. They'll work more efficiently thanks to Mac OS X's superior software and stability, and they'll need expensive and powerful machines to be productive anyway. If interoperability is a concern, don't fret; they can use any Microsoft Windows software your other employees use with emulation software like Parallels and VMWare, though licenses for those programs will cost you even more. 

Linux 

Linux is not produced or supported by any one company. Instead, it's developed by a loose community of computer software experts working at different companies all over the world. It's an open source operating system, which means anyone who installs it can make changes to it if they know how.

Software developers, engineers, and other highly technical professionals are the most likely to be comfortable with Linux. It gives them unrivaled access to its inner workings, it's very resource-efficient, and it's an ideal slate on which they can emulate other environments for testing. Because it's open source, they can create custom development tools and integrate them into the system. When these professionals request Linux, it's not a pie-in-the-sky idea; it could bring big improvements to their workflow and productivity.

You should be aware that support options for Linux are limited because of the decentralized nature of open source projects; consider it DIY (Do-It-Yourself) computing. This is fine if the computers are mainly used by technical people who know them inside and out, but Linux is not ideal for everyone. It's very commonly used on network servers and computers dedicated to engineering and scientific research, but it's not as often used by office receptionists.

Non-technical employees will be more comfortable with Windows or Mac computers, but there's another benefit to Linux: It's free. It also runs comfortably on low-end hardware. If you have a system administrator who is able to support Linux, you can save money by using it. Just know that if you plan on collaborating frequently with Windows or Mac users, you'll experience occasional hassles unless you spend money on emulation software.