The basic idea behind open source is very simple: When programmers can read, redistribute, and modify the source code for a piece of software, the software evolves. People improve it, people adapt it, people fix bugs. The practical advantages of open source are long-known in technical circles. In fact, they are a reason for the rapid development of the Internet and the World Wide Web, going back more than twenty years.

Open Source Initiative (OSI) is a non-profit corporation dedicated to increasing awareness of the benefits of open source for commercial users and developers, managing and promoting the use of the "OSI Certified" mark for software, and fostering discussions of open source licensing practices.

What the "OSI Certified" mark means

We authorize the mark "OSI Certified Open Source Software" to be used by a software distributor to label

software (not licenses alone) distributed under an OSI approved license provided that source code is included in the form used by the authors of the software.

The mark indicates that the requirements of the The Open Source Definition are met by the license, and the distribution does not prevent the activities which make open source so powerful and beneficial. [How to certify]

Learn more about open source. Did you know that Linux and Apache are two of the packages reaping open source payoffs? There are literally tens of thousands of software packages which qualify as open source, including many commercial products. [Some well-known examples.] You can read a brief history of the open-source concept, and browse links to other resources related to open source. We also maintain a page answering Frequently Asked Questions.

This site is still evolving as we think through the implications of open source in the commercial world. We don't claim to have all the answers yet, so mail us with your thoughts and criticisms. Also, please send us URLs of articles and papers on commercial trials of the open source model, on open source software including such packages as Linux and Apache, and related topics.

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