What Is Linux
Linux is an independent implementation of the POSIX operating system specification (basically a public specification of much of the Unix operating system) that has been written entirely from scratch. Linux currently works on IBM PC compatibles with an ISA or EISA bus and a 386 or higher processor. The Linux kernel was written by Linus Torvalds from Finland, and by other volunteers. Many of the utilities are from the Free Software Foundation's GNU project. Add to this basic definition the fact that everything is essentially free (more on this later) and you have yourself a complete Unix-like operating system that can run on the average personal computer.
Although Linux can run on a 386SX based system with 2MB of RAM and 40MB of disk storage this won't show you the power of the system. The average system consists of 8MB of RAM and 300-1000MB of disk storage along with the usual array of peripheral equipment such as VGA monitors, keyboards, floppy disks and interface boards. Where do you get it? If you are connected to the Internet you can download it for free. With its current size, however, purchasing a packaged version may be a better alternative. Packaged versions of Linux are available on floppy disks, cartridge tape and CD-ROM and range in price from $30 upward depending on what is included.
Although the initial Linux effort was started as a more or less hobby project, commercial distributions and commercial use of Linux systems are becoming more common. It is expected that Linux will play an important role in the current computer industry trend of downsizing as a single Linux system running on standard PC hardware can act as a server for multiple systems as well as offering a low-cost alternative to proprietary workstations running the Unix operating system.
Most of the development of the Linux system has taken place in semi-public forums on the Internet where current readership of the Linux newsgroups is around 100,000. This effort has grown to this substantial size in only about 2 years. Over the next two years, we expect to see an amazing growth in both the number of Internet users and the number of Linux users. In fact, Linux will be the tool that many people choose in order to get themselves connected to the Internet.
Today Linux is primarily a Unix-like system. But an emulator exists that allows it to run MS-DOS based applications and an interface is currently being developed that will allow Linux to run Microsoft Windows applications directly using the capabilities of the X-windows system which comes with many Linux distributions. Thus, in the near future, Linux will offer both native applications and the capability to run many of the existing PC-based applications all on one platform.
Up to this point, most of the work on Linux has been done in a reasonably public fashion. Usenet newsgroups and various electronic mailing lists have been the place where design decisions are made, bugs are reported and new releases are documented. In fact, it is this open forum that has made if possible to develop such an amazing product by a team of volunteers spread around the globe in such a short time frame.
As the Linux user community continues to grow we see an amazing number of newcomers entering the Usenet discussions each month. Many of these newcomers are seeking answers the the eternal questions: what hardware do I need, where can I get a copy of Linux and why doesn't something work. I expect for every question asked on one of these newsgroups there are at least ten others that go unasked and probably unanswered.
This is one of the places where LJ fits in. We plan to become a resource where people can find the answers to questions. And being a magazine instead of a discussion group we can assemble the needed answers andmake them available in a form that can be accessed by more people in more locations. Yes, some people have laptops and cellular phones that they can take on the bus but it still remains easier to hand a friend a magazine than help him or her get up to speed on using Usenet news readers.
We see this part of our audience as being two groups. Lots of the current Linux users have worked professionally with Unix. The other segmentis the DOS user who wants to upgrade to a multi-user system. With a combination of tutorials and technical articles we hope to satisfy the needs of both these groups. The second audience we want to address is the commercial user. As I have been talking to people about LJ I find that I need to be an evangalist. For example, I have talked to hardware vendors and manufacturers of diagnostic tools. Only one had heard of Linux but all of them are somewhere between interested and excited when I told them the Linux story.
Many people question how something can be “free” and still be able to make money change hands. The vendors understand. Getting more Linux systems out there means selling more computers, more hard disks, more ethernet cards, more communications boards and more consulting. For comparison, look at your CD collection. For most of us, the cost of the CD player is insignificant in comparison to the cost of the CDs we have purchased. Linux is like the CD player and will encourage people to buy what they need to support it.
Besides making money, Linux can offer better alternatives for the end user. For example, I did some consulting a few years ago for a small business. They needed a multi-user system with a database, word processing and some document layout software. And they had a small budget. The solution they got was a single 386-based system with a fewterminals running SCO Xenix, troff and a database. Today they need to add more horsepower and would like to network an MS-DOS based system to what they have.
The upgrade path for them is to purchase more computers, more copies of Xenix (or Unix), TCP/IP communications software, Network File System software and some Ethernet boards to connect everything together. In other words, spend more money than they did initially to add the functions they need.
If their system was based on Linux they would already have TCP/IP and NFS as it comes with Linux. And Linux is not licensed on a per system basisso they wouldn't need to purchase more licenses. Thus, for the cost of the computers and Ethernet boards they could expand their network. They could probably get the system they need for not much more than the cost of the system they had to settle for.
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