opensource

Open source refers to a development model and licensing approach in which the source code for software is made publicly available for use, study, modification, and redistribution. Projects operating under open-source licenses are typically developed in a collaborative manner by individuals and organizations around the world, and the resulting software is often distributed at little or no cost. The term open source emerged in the 1990s from the free software and open-source movements, and it is commonly used to describe software that meets criteria set by organizations such as the Open Source Initiative.

Licensing is central to open source. Open-source licenses grant rights to view, modify, and redistribute the code, subject to conditions. Some licenses are permissive, allowing broad reuse with few obligations (for example MIT or Apache 2.0). Others are copyleft, requiring that derivative works also be distributed under the same license (for example GPL). The Open Source Initiative maintains a widely used definition of open source, while the Free Software Foundation emphasizes freedom to run, study, modify, and share software.

Open-source development is characterized by transparency, collaborative governance, and merit-based leadership. Development occurs in public repositories, issue trackers, and mailing lists. Benefits include faster development cycles, interoperability, and broader participation. Open source underpins much of modern software infrastructure, including operating systems, web servers, databases, and programming languages.

Critics point to questions of sustainability, quality control, and security in distributed projects, while proponents argue that open review and modular design improve reliability. License proliferation and compliance can be complex for organizations. Open source continues to evolve with models such as corporate sponsorship, foundations, and dual-licensing.