Who's Using Linux? (Running Linux, 4th Edition)

1.3. Who's Using Linux?

Application developers, system administrators, network providers, kernel hackers, students, and multimedia authors are just a few of the categories of people who find that Linux has a particular charm.

Unix programmers are increasingly using Linux because of its cost — they can pick up a complete programming environment for a few dollars and run it on cheap PC hardware — and because Linux offers a great basis for portable programs. It's a modern operating system that is POSIX-compliant and looks a lot like System V, so code that works on Linux should work on other contemporary Unix systems.

Networking is one of Linux's strengths. It has been adopted with gusto by people who run large networks, due to its simplicity of management, performance, and low cost. Many Internet sites are making use of Linux to drive large web servers, e-commerce applications, search engines, and more. Linux supports common networking standards, such as Network File System (NFS) and Network Information Service (NIS), making it easy to merge a Linux machine into a corporate or academic network with other Unix machines. It's easy to share files, support remote logins, and run applications on other systems. Linux also supports the Samba software suite, which allows a Linux machine to act as a Windows file and print server. Many people are discovering that the combination of Linux and Samba for this purpose is faster (and cheaper) than running Windows 2000.

One of the most popular uses of Linux is in driving large enterprise applications, including web servers, databases, business-to-business systems, and e-commerce sites. A large number of businesses are discovering that Linux is an inexpensive, efficient, and robust system capable of driving the most mission-critical applications. The fact that Linux can be readily customized — even down to the guts of the kernel — makes the system very attractive for companies that need to exercise control over the inner workings of the system. Linux supports RAID, a mechanism which allows an array of disks to be treated as a single logical storage device, greatly increasing reliability. The combination of Linux, the Apache web server, the MySQL database engine, and the PHP scripting language is so common that it has its own acronym — LAMP. We'll cover LAMP in more detail in Chapter 18.

Kernel hackers were the first to come to Linux — in fact, the developers who helped Linus Torvalds create Linux are still a formidable community. The Linux kernel mailing lists see a great deal of activity, and it's the place to be if you want to stay on the bleeding edge of operating system design. If you're into tuning page replacement algorithms, twiddling network protocols, or optimizing buffer caches, Linux is a great choice. Linux is also good for learning about the internals of operating system design, and many universities are making use of Linux systems in advanced operating system courses.

Finally, Linux is becoming an exciting forum for multimedia. This is because it's compatible with an enormous variety of hardware, including the majority of modern sound and video cards. Several programming environments, including the MESA 3D toolkit (a free OpenGL implementation), have been ported to Linux. The GIMP (a free Adobe Photoshop work-alike) was originally developed under Linux, and is becoming the graphics manipulation and design tool of choice for many artists. Many movie production companies regularly use Linux as the workhorse for advanced special-effects rendering — the popular movies Titanic and The Matrix used "render farms" of Linux machines to do much of the heavy lifting.

Linux also has some real-world applications. Linux systems have traveled the high seas of the North Pacific, managing telecommunications and data analysis for an oceanographic research vessel. Linux systems are being used at research stations in Antarctica, and large "clusters" of Linux machines are used at many research facilities for complex scientific simulations ranging from star formation to earthquakes. On a more basic level, several hospitals are using Linux to maintain patient records. One of the reviewers of this book uses Linux in the U.S. Marine Corps. Linux is proving to be as reliable and useful as other implementations of Unix.

So Linux is spreading out in many directions. Even naive end users can enjoy it if they get the support universities and corporations typically provide their computer users. Configuration and maintenance require some dedication. But Linux proves to be cost-effective, powerful, and empowering for people who like having that extra control over their environments.


1.2. A Brief History of Linux		1.4. System Features