What is Linux?

Linus Torvalds' now famous Usenet post on October 5th 1991

You may not know who Linus Torvalds is, but Microsoft sure does.

More than Steve Jobs, Scott McNealy, or Larry Ellison, this Finnish programmer and his trusty Linux operating system have the best shot at breaking Microsoft's death grip on the computing industry.

What makes the Unix-like Linux so winning? It's speedy, stable, built to run on many kind of computers, and - most importantly - Linux is free. It's free to use and free to sell, which has created stiff competition among Linux developers, and contributed to Linux's rapid improvement.

In fact, Linux has become so good that it's sneaking its way into mainstream businesses, and proving to be a viable alternative to Windows NT. That's because Linux lets businesses run a reliable server or workstation on legacy hardware - unlike the resource-hogging NT, which requires newer, more robust hardware. But will Linux ever run on consumers' desktops? Only time will tell.

One thing's for sure: Linux is more than geek chic. While it still has a few wrinkles, this once-obscure OS is here to stay. What makes Linux so special, and how will it succeed against the bigwigs in Redmond? Read on.

In the beginning, there was Minix, and it was good. But not good enough for Linus Torvalds. Created in Amsterdam by Vrije University's Professor Andrew Tannenbaum, Minix is a Unix-look-alike operating system that runs on PCs. One of the students who used Minix at the University of Helsinki was Linus Torvalds. He appreciated Minix, but thought he could do better. In 1991, Torvalds created his own Unix clone and one of his friends named it Linux after Linus and the Unix OS it resembles.

Distinct personality

Torvalds' new operating system, like Minix, did not use any code from commercial Unix vendors, such as AT&T, so Torvalds could distribute Linux across the Net free of charge. And that he did: on October 5, 1991, Torvalds posted a now-famous call to arms on the comp.os.minix newsgroup, announcing that the Linux source code was available and asking other programmers to help him develop it.

At the time, Linux seemed pretty half-baked; it ran only a very limited set of Unix commands, such as bash, gcc, and gnu-make. But thanks to the work of Torvalds and thousands of volunteer programmers across the Internet, it soon became a top-notch operating system.

In fact, by the time Torvalds released Linux 1.0 in 1994, the OS was stable and full of advanced features, such as pre-emptive multitasking (the ability to split CPU resources among multiple applications), symmetric multiprocessing (the ability to split tasks between multiple CPUs), and full POSIX compliance (which means it's easier to create Linux versions of POSIX-compliant applications). It even had its own mascot, which Torvalds described in a Linux Online quote as "a loveable, cuddly, stuffed penguin sitting down after having gorged itself on herring."

Collaborative development

With their cuddly mascot cheering them on, Linux's world-wide development team soon began to produce results. By 1996, they had created Linux versions for several different types of hardware, from the Atari ST to the Macintosh.

Why all of the enthusiasm? Partly because Linux was distributed under the GNU Public License, or GPL. That meant that anyone could copy, use, modify, and sell Linux software, provided that its developers received proper credit, and that any changes to the source code were made public.

Making money

It wasn't long before someone figured out how to make money with Linux. As soon as the Linux kernel - the heart of the OS - became available for free on the Net, several vendors began to sell CDs of Linux drivers, applications and utilities. These are called distributions.

Though you can download most of this software from the Internet, the files are large, and the lengthy download times usually justify the £20 to £50 price of the CD. Plus, most Linux distributions offer something unique: S.u.S.E. Linux, for instance, comes with a central configuration tool for setting up hardware and networking.

But since any modifications to Linux must be made public, Linux distributors' competitive advantages have been short-lived. They must constantly re-innovate to stay ahead of the curve.

The result? Linux has improved faster than anyone could have imagined. Today, Linux runs on an estimated 7 to 8 million computers, and thousands of programmers work on both the kernel and the Linux applications. The Linux kernel is now well into version 2.2, and compatible with an enormous amount of hardware, including the Alpha, Amiga, Atari, IBM, Intel, PowerPC/Macintosh, SGI, and Sun SPARC platforms. On all of these systems, Linux generally runs faster and offers more stability than other operating systems.

Linux heads

Despite all of its obvious advantages, though, Linux is still most popular with IT administrators and hard-core hackers. But that's starting to change.

Programmers in training sometimes use Linux on their home PCs to familiarise themselves with Unix applications and administration. And, many ISP's run Linux on their servers because it's free, and because it speeds the performance of their legacy hardware. Linux is even popping up in the corporate world, where IT workers sometimes manage to sneak in a Linux box as an intranet, mail server or workstation.

Quick changes

Linux will continue to rapidly improve. It must, because unlike Microsoft and Apple, which are the sole vendors of their respective operating systems, Linux has several vendors competing for market share. The only way a Linux vendor can avoid being shut out by other Linux vendors is to innovate and improve the product quickly.

Linux is remarkable for the international scope of its development community and the level of co-operation among its members. While UNIX fragmented into dozens of versions, confusing managers and programmers, Linux has held together as a single operating system capable of running on all kinds of computer architectures. It provides a UNIX-compatible development platform that allows developers to choose the best machine possible and then add the operating system they need to be productive.

To make sure the rapidly changing Linux distributions remain compatible, a group called the Linux Standard Base was formed. This organisation ensures that the various distributions will be able to run the same apps and inter-operate properly.

Windows like GUI

In 1998, a Windows like graphical user interface was released for Linux. It's called KDE - or the K Desktop Environment. User's of well known GUI's such as Windows and MacOS will feel immediately at home with KDE.

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Applications

Linux will soon support more applications, too. Oracle and Informix recently announced Linux versions of their server software, quelling any doubts of Linux's viability in the workplace. And, for end users, big names, such as Corel's WordPerfect are already available.

If Linux becomes truly user-friendly, that, in combination with its already great performance and dirt-cheap price, will make it a hit with corporations and consumers alike.

The secret to Linux's success is that, unlike Microsoft and its other competitors, who must turn a profit from the sale of their product, the Linux movement is almost invulnerable to price cuts and marketing campaigns. After all, it's free. Linux distributors such as Red Hat do need to make a profit, but their income come more from support contracts and documentation than from the sale of Linux CDs.

Free for all

Ultimately, Linux has turned the tables on the computing industry. It calls into question the benefit of charging money for an operating system, and Microsoft, Sun, and others like them will have to answer.

No doubt Linux will radically change the future of computing - a future of free and open operating systems - running on the hardware of your choice.