Security - Linux is Open Source Software, while Windows is not. The simplest benefits of Open Source Code to demonstrate are increased security, reliability and functionality; because users of Open Source are readily able to identify and correct problems with the programs and to submit their own enhancements for incorporation into the program. Closed Source systems enjoy none of those benefits.
Scalability - Systems implemented under Linux can be cloned limitless times without paying additional software licensing fees - With Windows, you pay for each installation/workstation/server/cpu.
Power - Linux is made with the Unix design philosophy, which dictates that system tools are small and highly specialized. The result is an incredibly powerful and reliable system, limited in capability only by the user's imagination and ability to integrate the Unix utilities. The Windows philosophy is to create unwieldy swiss army knives, limited in capability by how many features the user purchased on their particular knife. Diminished reliability is arguably a side effect of increased complexity. Thus with Windows, the case is often that you have tools that ALMOST do what you want them to, if they didn't crash.
Reliability - The architecture of Linux is superior to Windows because critical operation system functions are implemented in such a way that buggy programs can't cause the computer to become unstable and crash. In fairness, though not quite as robust as Linux, Windows 2000 and Windows XP are much improved over Windows 9x and Windows Millenium Edition.
Advanced Capabilities - In addition to the system utility tools from the Unix world, Linux usually comes with the Apache Webserver, an email server, router/firewall capabilities and SQL databases. These are extras costing up to thousands of dollars on Windows. There IS free software to do these jobs on Windows, but it has mostly been adapted from Linux and loses some functionality when ported to Windows.
Compatibility - Linux is POSIX Compliant which means that applications developed for Linux can be operated on other POSIX compliant Unix derivatives with a minimum of reworking.
Support - For persons not familiar with the Open Source Community, the quality of free technical support on the internet may come as a shock. Sometimes knowing enough to ask the right questions can be a problem, but overall the best and the brightest are there to assist you at no charge when you run into problems that can't be solved by reading the documentation included with Linux. With Windows or other commercial software, your manufacturer support is only free for a limited time and is often of little value anyways.
Not Single Source Software - Linux is distributed by several companies, giving consumers to pick and choose the flavor that best suits their needs. Windows is the product of a single company, Microsoft Corporation. Windows users have no choice but to accept what Microsoft offers.
Rate of Advancement - Linux has and will continue to advance at a rate impossible for a close development project such as Microsoft Windows to sustain. A few factors driving this rate of progress are (in no particular order): the number of active developers; quantity and quality of feedback from the field; short development cycle from development team to the end user; absence of corporate "meddling" in the design process; independently developed open source subsystems frequently incorporated into Linux, giving it quantum advances in a short time.
Cost - That Linux is FREE deserves honorable mention and a bit of explanation. You can package and sell Linux for money. The competing Linux distributions all provide slightly different feature sets beyond the core system, including canned e-commerce solutions, printed manuals and phone support options. There is no rule that says you can't make money distributing Linux. For those who choose to download and install free distributions from the Internet, Linux is truely free. Some cynics have proclaimed, "Sure Linux is free now, but the Linux People will start charging for it once it catches on!". That statment is completely false. No single person or organization controls Linux, so that will never happen. In the unlikely case that Linus Torvalds (the author of Linux) adds some proprietary code and proclaims that all future releases will be $99.99USD, someone will simply take the latest "free" version and possibly rename it to Spin-UX. Then all the volunteer developers and contributors will jump on that bandwagon. Spin-UX will diverge from its Linux roots, over time becoming better supported and more advanced, rendering its ancestor obsolete, except possibly for purposes specifically addressed by that hypothetical proprietary added code. Furthermore Linux is covered by the Gnu Public License, stating that it and all derivative works must be distributed with the source code. This makes it extremely unlikely that anyone will wield monopolistic power in the Linux Sector.
To conclude this hopefully persuasive bit of Linux Advocacy, it must be stated that an Operating System without suitable Applications is of little use. There are free web browsers and email clients for Linux like the Mozilla Firefox, as well as the free OpenOffice.org product from Sun Microsystems. OpenOffice.org includes the traditional productivity applications: Word Processing, Spreadsheet and Database with a lot new advanced features. Corel Office is also available for Linux at little or no charge.
