Open Source refers to software whose source code is publicly available, allowing anyone to view, modify, and distribute it. Open-source software (OSS) promotes collaboration, transparency, and community-driven development.

  • Key Idea: Users can freely use, modify, and share the software.
  • Examples: Linux, Git, Python, Apache, PostgreSQL.

Popular Open Source Licenses

  • GNU General Public License (GPL): Requires derivative works to be open-source (copyleft).
  • MIT License: Very permissive; allows modification and distribution without restrictions.
  • Apache License: Similar to MIT but includes patent protections.
  • BSD License: Permissive, with minimal restrictions.
  • Creative Commons (CC): Often used for non-software works.

GPL vs. MIT: GPL ensures modifications remain open-source, while MIT allows proprietary modifications.