A free software program published under a license allowing free use is called open-source software. This software grants users the right to run, modify, and distribute the source code, promoting collaboration and community development. Examples include Linux, Apache, and LibreOffice. By encouraging users to contribute improvements and share knowledge, open-source software leads to innovation and rapid problem-solving. It also fosters an ecosystem where users are not locked into proprietary systems, providing greater flexibility and control over their software environments.