Open source is a development method for software that harnesses the power of distributed peer review and transparency of process. The promise of open source is better quality, higher reliability, more flexibility, lower cost, and an end to predatory vendor lock-in.

The Open Source Initiative (OSI) is a non-profit corporation formed to educate about and advocate for the benefits of open source and to build bridges among different constituencies in the open-source community.

One of the most important activities is as a standards body, maintaining the Open Source Definition for the good of the community. The Open Source Initiative Approved License trademark and program creates a nexus of trust around which developers, users, corporations and governments can organize open-source cooperation.

Open Source Software (OSS) may be used freely by commercial organsiations.  The are may viable Open Source packages from file server, to mail servers, internet servers, office automation tools, web browsers and email clients, thus providing a viable alternative to commercial software.

Open source software began as a marketing campaign for free software. OSS can be defined as computer software for which the human-readable source code is made available under a copyright license (or arrangement such as the public domain) that meets the Open Source Definition. This permits users to use, change, and improve the software, and to redistribute it in modified or unmodified form. It is very often developed in a public, collaborative manner.

Open source licenses define the privileges and restrictions a licensor must follow in order to use, modify or redistribute the open source software. Open source software includes software with source code in the public domain and software distributed under an open source license.

Examples of open source licenses include Apache License, BSD license, GNU General Public License, GNU Lesser General Public License, MIT License, Eclipse Public License and Mozilla Public License.

NPS encourages its clients to take advantage of OSS wherever possible: