According to Wikipedia, “Open Source is a set of principles and practices on how to write software. Literally ‘open source’ means the source code is available to the users. The Open Source Definition, which was created by Bruce Perens^[1] and Eric Raymond and is currently maintained by the Open Source Initiative, adds additional meaning to the term. One should not only get the source code but also have the right to use it. If the latter is denied the license is categorized as a shared source license.”

Many popular web applications. software applications and websites are open source.  Here are just a few examples:

• osCommerce
• CMS-MS
• PHPNuke
• Wikipedia
• Mozilla Foundation
• Drupal
• Joomla
• Linux
• mySQL
• PHP
• OpenOffice.org

Open Source web applications should be considered by any web entrepreneur in that they can present significant advantages over their commercial, closed source alternatives.  Open Source software typically has a large, vibrant, and more dedicated group of users supporting and communicating about the product.  The software usually has less time between flaw discovery and a fix.  Additionally, because the source code is available, you can analyze everything yourself and be confident in security.  On the flip side, commercial software is typically supported regularly by a company and there is more of an incentive and guarantee that updates will occur.  Additionally, by not exposing the source code, hackers can’t easily learn the application’s security flaws.

In my opinion, Open Source is also great because you are no longer relying on one company to provide support and updates. No longer are you hostage to the feature updates they they think is worthwhile.  With Open Source, the power is placed in the hands of the users, so updates are typically more frequent and widespread.

Open Source shouldn’t be chosen simply because of cost (free!).  It should be stacked up against its competition and rated based on cost, community, features, etc…  More often than not, an Open Source solution can be optimized and enhanced to meet your needs while providing a lower cost of entry.  For instance, if you are looking for a comprehensive and powerful e-commerce system, you could install a highly optimized version of osCommerce, an Open Source e-commerce system, and your end-result could end up more powerful and very different from the stock Open Source system, but now you have an application that can be supported by a wide number of developers and companies.  It’s what we call “Open Source Optimized Solutions” and we use solutions like these for content management systems, e-commerce systems, etc…

Related Reading:

• Free Software and Open Source software (Where to find) - from WikiHowTo
• FAQ - Getting Started With Open Source Development
• 5 Ways to Contribute to Open Source Projects Without Coding
• Anarchism Triumphant: Free Software and the Death of Copyright — Eben Moglen, Professor of Law and History at Columbia University
• Brief History of the Open Source Movement
• “the” definition of open source
• The dotCommunist Manifesto — Eben Moglen
• Open Source Initiative (OSI) — a list of available licenses
• Open Sources: Voices from the Open Source Revolution — an online book containing essays from prominent members of the open source community
• Why “Free Software” is better than “Open Source” — a later essay from Richard Stallman
• Free / Open Source Research Community — Many online research papers
• Jan 2006 TPOSSCON talk: “How OSS Improves Society” Aaron Siego speaks at the 2nd Trans-Pacific Open Source Software Conference in Honolulu, Hawaii.
• Why Open Source Software / Free Software (OSS/FS, FLOSS, or FOSS)? Look at the Numbers! - large collection of related quantitative studies
• “Lessons from Open Source”, by Jan Shafer
• Free Software Definition, Free Software Foundation Definition of free software by Richard Stallman
• Whence The Source: Untangling the Open Source/Free Software Debate, essay on the differences between Free Software and Open Source, by Thomas Scoville
• Degrees of Openness article explaining the different aspects of openness in computer systems, written by Adrien Lamothe, on the O’Reilly Network.
• Open Source Software List
• Open Source Community
• Differences between open source and free software as interpreted by Slackware
• Berry, D M (2004). The Contestation of Code: A Preliminary Investigation into the Discourse of the Free Software and Open Software Movement, Critical Discourse Studies, Volume 1(1).
• Benkler, Yochai, “Coase’s Penguin, or, Linux and The Nature of the Firm. Yale Law Journal 112.3 (Dec 2002): p367(78) (in Adobe pdf format)
• An open-source shot in the arm? The Economist, Jun 10th 2004,
• SDForum Distinguished Speaker talks on Open Source Software by Guido van Rossum, Howard Rheingold, and Bruce Perens, 2005.