Open source describes practices in production and development that promote access to the end product’s source materials. Some consider open source a philosophy, others consider it a pragmatic methodology. Before the term open source became widely adopted, developers and producers used a variety of phrases to describe the concept; open source gained hold with the rise of the Internet, and the attendant need for massive retooling of the computing source code. Opening the source code enabled a self-enhancing diversity of production models, communication paths, and interactive communities. Subsequently, a new, three-word phrase “open source software” was born to describe the environment that the new copyright, licensing, domain, and consumer issues created.
The open source model includes the concept of concurrent yet different agendas and differing approaches in production, in contrast with more centralized models of development such as those typically used in commercial software companies. A main principle and practice of open source software development is peer production by bartering and collaboration, with the end-product, source-material, “blueprints” and documentation available at no cost to the public. This is increasingly being applied in other fields of endeavor, such as biotechnology.
Open source software is software whose source code is published and made available to the public, enabling anyone to copy, modify and redistribute the source code without paying royalties or fees. Open source code evolves through community cooperation. These communities are composed of individual programmers as well as very large companies. Examples of open-source software products are:
Programming language
PHP - Scripting language suited for the web
OS
GNU Project — “a sufficient body of free software”
Linux — operating system kernel based on Unix
OpenBSD — operating system derived from Unix
FreeBSD — operating system derived from Unix
OpenSolaris — Unix Operating System from Sun Microsystems
Symbian — real-time mobile operating system
Server
Apache — HTTP web server
Tomcat web server — web container
Mediawiki — wiki server software, the software that runs Wikipedia
Alfresco — content management system
RenovatioCMS — content management system
Joomla — content management system
Drupal — content management system
TYPO3 — content management system
WordPress — blog software
MongoDB — document-oriented, non-relational database
Eclipse — software development environment comprising an integrated development environment (IDE)
Moodle — course management system or virtual learning environment
openSIS — open source Student Information System
Client software
osCommerce — ecommerce
PeaZip — File archiver
Mozilla Firefox — web browser
Mozilla Thunderbird — e-mail client
OpenOffice.org — office suite
Stockfish — chess engine series, considered to be one of the strongest chess programs of the world
7-Zip — File archiver
And many, many more