I've heard it all before: Unix will control the world's desktop computers! No, NextStep will rule! Wait a minute, make that OS/2 — OS/2 will bury Microsoft Windows!

Not one of these predictions has come to pass. Instead, it's the McDonald's of software, Microsoft Windows, that's become the de facto standard for business computing. But now there are echoes of a new mantra in the land of computers: Linux, Linux, Linux.

Linux is yet another operating system, and tech heads are predicting that it will one day take over the computing world. They might be right. This time, the upstart is supported by thousands of volunteer programmers, hundreds of millions of dollars in venture capital, and stratospheric stock valuations.

And there's more. Unlike past contenders for the title of heavyweight operating system, Linux is free. Anyone can download Linux from the Internet, and it works on just about every type of computer. Moreover, Linux is stronger, tougher, faster, and more secure than Windows — at least, that's what Linux evangelists claim.

Linux's rise has been truly remarkable. But even until recently, Linux was mostly confined to back-office computers. Now, however, several hardware and software companies are trying to convince the rest of us that we should use Linux too.

Can we depend on a free operating system to run all of our business applications? To find out, I spent a few weeks installing Linux on different systems and sampling Linux-based software packages. After much poking and prodding, I'm primed to take on 10 of the most frequently asked questions about Linux. Here, then, are the FAQs.

1. What is Linux, and is it really free?

Linux is the underlying software code, or "kernel," that tells a computer what to do and how its software should behave. The prime mover behind Linux is Linus Torvalds, a software engineer who, in 1991 — while still a student at the University of Helsinki — began working with Minix software to create a Unix-like operating system from scratch. But he hasn't been going it alone. For the past nine years, thousands of programmers have worked on Linux (pronounced LINN-ucks), developing a free operating system that anyone can download from the Net.

Linux is free in more ways than one. In Linux's case, "free" also means "transparent." That is, anyone can look at the software's underlying components — which in most other operating systems are kept top secret — make changes, and thus write better programs or fix problems easily. That's because Linux hews to an open-source model, where there are no licensing fees for looking at, adapting, and fixing the code. And that's a very big deal, because anybody can use Linux software to create embedded applications, such as programs that are customized for specific work requirements. (This comes with a caveat: If you alter the source code — that is, the main components — of the Linux software, you must in turn make the source code of any software you write freely available to other programmers.)

2. Enough about code. What about Linux's "look and feel"?

Although there's just one stable kernel version of Linux, there are several different graphical interfaces from which to choose, each with its own special features. Most of these friendlier, "Linux-for-the-rest-of-us" packages are based on one of two popular graphical user interfaces, or GUIs.

KDE (K Desktop Environment) was an early graphical interface brought over from the commercial Unix world. At first, many Linux proponents resisted KDE, because some of the tools that programmers used to create programs and improve the software in KDE were not "open" — that is, a license was required to use them.

Consequently, a collection of volunteer programmers decided that a completely open and free GUI was necessary. So they created GNOME (meaning GNU Network Object Model Environment), a graphical front end that's comparable to KDE, but with a lot more flexibility. With GNOME (pronounced Guh-NOME), you can change and adjust nearly every aspect of your system. Since GNOME was released, KDE backers have also worked to distribute KDE tools for free. Consequently, retail versions of Linux are usually wrapped in either a KDE or a GNOME graphical interface.

To make things more confusing — but also more flexible — most GUIs work with several different "windows managers." These are the elements that you actually see on the screen, such as colored menu bars and cutesy icons. For example, GNOME works with several windows managers. One of these, called Enlightenment, looks very much like Microsoft Windows 98. You can also give GNOME a Macintosh-like interface, if that's what you're used to.

All of this is free: Linux, the GUI, and the windows manager. Most have been bundled together in a single package. Often dubbed "distros" (for "distributions"), these packages usually include an automated installation program, the Linux kernel, a GUI such as KDE, and several windows managers. Distros built for the average computer user include Red Hat Linux 6.1, Caldera's OpenLinux 2.3, and Debian GNU/Linux.

Coordinates: Linus Torvalds's home page, www.cs.helsinki.fi/~torvalds; Linux Online, www.linux.org; KDE, www.kde.org; GNOME, www.gnome.org

3. What do I get when I download Linux?

You can download a perfectly serviceable, free-of-charge version of Linux from the Web, along with the associated installation libraries. Even most of the commercial versions — those from Caldera and Red Hat, for example — are available free of charge on the Web. But unless you're a supergeek, I would not recommend taking the download path. First, the free Web version doesn't come with free technical support. Second, downloading and installing the software can be a serious challenge. (Even Torvalds reportedly uses a commercial version of Linux.)

A smarter, hassle-free approach is to shell out the money for a commercial distribution of Linux. I tried several versions — ranging from $20 to $50 — and they all worked fairly well. The commercial packages all have added an easy-to-use front end, which means you don't have to enter arcane code words to get the operating system up and running.

4. Which Linux package is right for me?

Computer users who want to run Windows on the same system will find that Caldera's OpenLinux 2.3, which costs $50, is the easiest of the Linux packages to install. OpenLinux uses the KDE graphical interface and includes all of the major applications you will need, including Sun Microsystems's StarOffice 5.1, Corel's WordPerfect 8, and Netscape Communicator 4.6.

Installation of Red Hat Linux 6.1 wasn't quite as easy as Caldera's, but it still managed to find nearly all of my computer's internal components. In other words, I didn't have to tell it what kind of hard drive I have. Better yet, for $80, the Red Hat Linux 6.1 Deluxe package gives you a choice of using either the KDE or GNOME interface. And it features a dial-up network connection that makes accessing the Internet as easy as it is from Windows. But what I most appreciated was Red Hat's free month of technical phone support. Caldera charges you for technical-support calls.

The much-ballyhooed release of Debian GNU/Linux — with its affordable $20 price tag — is supported by Silicon Graphics, O'Reilly & Associates, and VA Linux Systems Inc. But Debian GNU/Linux is a noncommercial version of the operating system — and in some ways, a step backward. Although it uses the GNOME interface, Debian's installation is much more awkward than Red Hat's or Caldera's. If you don't feel comfortable telling Debian what kind of hard drive you have, Debian isn't for you. And getting it to work alongside Windows on the same machine requires a lot of futzing around.

Coordinates: Caldera Systems Inc., www.caldera.com; Red Hat Inc., www.redhat.com; Debian, www.debian.org

5. We use several different systems in our office. Does Linux really work on any kind of computer?

Just about. According to the specs, the minimum PC requirements for Linux are an Intel 386 computer with about 4 MB of ram. But to run the graphical interface and to have enough speed and space for your work, you should have at least a 486 (or a Pentium) machine with 64 MB of ram and a 600-mb hard drive. Linux will also run on PCs with processors from Advanced Micro Devices Inc. and Cyrix Corp.

If you've got a variety of computers in your office, you'll appreciate Linux's ability to run on a variety of non-Windows machines. For now, Linux supports Compaq Computer's (formerly Digital Equipment) Alpha-based systems, Sun Microsystems's Sparc stations, and even some of Apple's Macintosh systems. But not all versions of Linux support all of these machines. A case in point: Red Hat's latest release only supports Intel, Alpha, and Sparc systems. So make sure you check with the software vendor before you make a purchasing decision.

6. Will Linux work with all of the peripherals running on my computer?

Linux will run on a variety of computers, but it may support all of the features on a computer. Sometimes, internal components, such as built-in sound chips, will fail to work. And many peripherals, such as video cameras, aren't supported at all. As of this writing, the most prominent of Linux's drawbacks is this: It does not support USB (universal serial bus) peripherals.

That said, I did find that Linux supports hundreds of popular printers and many common business tools. For example, there are several free software programs that will connect your PalmPilot to a Linux computer and synchronize your address books. Still, the easiest way to ensure that the operating system works on your computer is to buy one with Linux already installed.

7. Which computers come with Linux already preinstalled?

Among the gaggle of specialty-hardware vendors that are offering Linux work-stations, the most prominent is VA Linux Systems. The company offers an array of computers, ranging from complete PCs for about $1,000 to full-blown work-stations with multiple processors that come with a price tag of more than $10,000. Another respected Linux-only computer seller is Penguin Computing.

The mainstream PC makers are also jumping on the Linux bandwagon. Last fall, Dell Computer began preinstalling Linux on many of its machines. Prices for these systems are not appreciably lower than those of similar systems outfitted with Microsoft Windows, but that may change as the competition starts to heat up. Expect to see computer-maker stalwarts Hewlett-Packard and IBM selling Linux desktop computers soon. Database giant Oracle is also joining the free-software legion: It plans to establish a separate company to sell Linux-based networked computers, which are expected to cost about $200 each.

Coordinates: VA Linux Systems Inc., www.valinux.com; Penguin Computing Inc., www.penguincomputing.com; Dell Computer Corp., www.dell.com/linux; Oracle Corp., www.oracle.com

8. How long will it take me to get comfortable using Linux?

It won't take forever. People who have used a Macintosh or a Windows machine will easily find their way around a Linux system that's been gussied up with GNOME or KDE. Onscreen icons launch programs with a click, and a movable tool bar calls up menus listing everyday programs. You'll have to unlearn some old habits, but many things work in familiar ways. For example, the software menu pops up in the bottom left-hand corner of the screen, and you can select applications like a CD player or a word processor from that list.

Even small tasks, such as renaming a file, are usually accomplished in the same way that they are in Windows. Macintosh users can even make the Linux GUI look like a Mac screen by selecting a different windows manager, or by putting the menu bar at the top of the screen and changing the borders to look like those of the MacOS.

All of this seems pretty seamless, until you decide to do something different — like reset the screen resolution or install a new program. Then you'll find yourself flipping through the Linux manuals for the right commands. That's because Linux still makes you go out to terminal mode to complete many tasks — which means you must alter a text command line to make changes to the system. Getting a new modem to work or installing a Linux program can be a chore until you learn the commands for setting up drivers and manually running software-installation routines.

9. Enough about the operating system — what about applications for Linux?

The main programs for Linux that run under KDE and GNOME can open and store many Microsoft Windows file formats. And there are enough solid software programs written for Linux to let you get your work done — with a couple of notable exceptions.

In the word-processing category, Corel's WordPerfect 8 ($70) for Linux is a winner. WordPerfect includes more than 5,000 clip-art images and supports more than 1,000 printers. If most of your work involves words, you won't have to make any sacrifices when you use Linux.

When it comes to all-in-one office suites, however, no big-name program is currently available for Linux. Corel says it plans to release its WordPerfect Office suite for Linux, which will reportedly include the popular Quattro Pro spreadsheet program.

Meanwhile, there's StarOffice 5.1, the perfectly serviceable office suite from Sun Microsystems. You can download it free of charge or pay $10 for the promotional CD-ROM. StarOffice includes a word processor, a spreadsheet, an email package, a calendar, and even a program for making presentations.

A Web browser is a must-have business tool, and Netscape continues to support Linux. The latest Linux version of Netscape Communicator 4.7 contains all of the essential elements of the Windows and the Mac versions, including email management and a Web-page composer. Most of the popular plug-ins, including RealNetworks's RealServer G2 media player, also work for people who are cybersurfing from a Linux machine.

What's missing? For one thing, no one has yet written a full-blown contact manager, such as Symantec's Act!, for Linux. Most versions of KDE and GNOME include an address book and calendar, but they lack advanced features that can track sales contacts and juggle multiple cross-references.

Coordinates: WordPerfect 8, www.corel.com; StarOffice 5.1, www.sun.com; Netscape Communicator, www.netscape.com; RealServer G2, www.realnetworks.com

10. So is Linux ready for prime-time business users?

In many respects, Linux passes the office test. After weeks of use, I managed to crash just one machine running GNOME. (Meanwhile, my Windows 98 machine continues to crash at least once a day.) And I was able to do most of my work on the Linux-equipped machines.

If you've got a dotcom business, Linux deserves a serious look. Linux is reliable and flexible — a plus for online businesses that must make weekly software changes to keep up with the Internet economy. Begin by having your developers use a few Linux boxes. Then start introducing the systems to other employees when the interface becomes more mature later this year.

But Linux gets a thumbs-down for small companies and home-based offices. Managing the operating system still requires some expertise. And Linux lacks most of the finishing touches that make it easier for users to install new software and solve small glitches on Windows PCs and Macs. What's more, until Corel and others release their applications for Linux-based machines, you'll be stuck with a limited number of business-software packages.

That said, take a good, hard look at Linux in four months or so. The speed at which applications are being written and improved on in the Linux world is absolutely astonishing, thanks largely to the Internet.

While older software companies such as Microsoft rely on employees ensconced in corporate campuses to churn out new bells and whistles for Windows, the legions of Linux volunteers use the speed and flexibility of the Internet to fine-tune and to improve the software. The result is that free Linux software upgrades get churned out online, 24 hours a day. The information superhighway has come full circle: Linux is changing the way the software that got us there in the first place is made.

Contributing Editor John R. Quain (jquain@fastcompany.com) appears regularly on CBS and on MSNBC.

Action Item: Linux Links

Here are three of the most user-friendly sites for learning more about leveraging Linux.

Linux Online (www.linux.org) If you're looking for Linux-compatible hardware or the latest software, start here. Linux Documentation Project (www.linuxdoc.org) Chances are that whatever you're trying to do with Linux, someone else has tried it before; those solutions are posted here. Linuxberg (www.linuxberg.com) This is a neatly arranged center for locating new Linux programs, from networking fixes to newly designed themes that will add some pizzazz to your desktop.

Sidebar: GNOME Guru

From his office in Mexico City, master programmer Miguel de Icaza cajoled, pleaded, and cranked out code to get GNOME — the free graphical front end for Linux — up and running smoothly. Here, de Icaza gave us the goods on GNOME.

What attracted you to Linux?

"When I started programming years ago, proprietary tools were expensive, yet they were of poor quality. But the free tools were great — anyone could access them and improve upon them. So I started to work on Linux, and I urged others to help."

What are you working on now?

"We're developing more end-user applications, such as office suites, that will also be free. We're also working on presentation programs, and I'm starting a company to write GNOME applications for Linux and other free systems."

Is Linux ready for individual computer users?

"It depends on what you want a computer to do. Linux is not quite ready for everybody's desktop, though in four to six months it might be. But even now, there's a project in Mexico that's distributing computers equipped with Linux and GNOME to 1 million students."

Coordinates: Miguel de Icaza, miguel@GNU.org; GNOME, www.gnome.org

Sidebar: Leap to Linux

Wondering whether your company can make the leap to Linux? David O'Dell, VP of engineering at Powerize.com, a Web site offering business research, has already taken some first steps. Here are five of his top-of-mind tips for converting your company to Linux.

Linux can handle customized applications. "Most custom applications can be built especially for Linux."

But consider your resources. "You need it support for Linux systems. If you don't have the technical-support people to work with it, don't even think about taking on Linux."

Check connections. "Even though the rest of my company uses Windows, our developers can still use Linux. They just use Lotus Notes to communicate and trade files with everyone else. Make sure that you can do the same before you invest in Linux."

Get it preinstalled. "Buying computers with Linux already installed will help your it department avoid many headaches."

Don't force Linux on everyone. "Our technical writers and sales staff don't use it, because the applications they're comfortable with aren't running on Linux yet."

Coordinates: David O'Dell, davido@powerize.com; Powerize.com, www.powerize.com

Sidebar: Linux on a Laptop

Because many components of notebook computers are custom-built, such systems present special challenges for Linux. To see how Linux would perform on the road, I took Red Hat Linux 6.1 for a test-drive on a Gateway Solo 9300. I restarted the Solo with Linux.

Nearly one-third of the screen remained blank! But I found an invaluable Web site, Linux on Laptops, where I located advice for fixing the display problem.

Then the internal modem died. Most built-in notebook modems require Windows software and therefore don't work with Linux. Fortunately, a PC Card modem works fine, so I plugged in an old 28.8-Kbps model to get online.

But the USB and Firewire ports didn't work. This is a major hole in Linux support. The next stable Linux kernel, version 2.4, is expected to close this gap.

Bottom line: Avoid putting Linux on a new notebook computer. It takes time for small fixes to be implemented for new hardware. An older laptop will probably work better with Linux.

Coordinates: Linux on Laptops, www.cs.utexas.edu/users/kharker/linux-laptop

Sidebar: Quain's Top 10

Are you thinking of installing Linux on your computer? Before you do, consider these 10 tips — and don't be afraid to consult the user's guide.

1. Set aside a weekend. It's possible to install Linux in a couple of hours. But chances are, you'll need more time.

2. Stick with even numbers. Stable versions of Linux end in even numbers (such as Linux 2.2); odd-numbered ones are works in progress.

3. Check tech support's business hours. Don't try to install Linux in the middle of the night — the folks in technical support may not be there to help you.

4. Check system compatibility. Make sure that all of the peripherals on your computer are supported by Linux, especially your modem.

5. Read all of the instructions carefully. Installing Linux is not as easy as installing Windows, so make sure you're familiar with all of the commands.

6. Back up everything. Before you start partitioning hard drives, copy your work to another machine or storage device.

7. Write down all of your system's specs. Make a list of system components, including the type of hard drive you use. Tech support might need that information if you run into problems.

8. When in doubt, "dual-boot." If possible, set up your system to work with Windows and Linux. That way, you can always go back to your old software.

9. Make sure you have enough disk space. The minimum is 300 MB, but plan on having at least 600 MB.

10. Seek advice online. Millions have already put Linux on their PCs. If you need help, look for it online.