The open-source movement influences software development by promoting collaboration, transparency, and community-driven improvements. By encouraging developers to share their code, the movement fosters an environment where innovations can be built upon collectively. This approach leads to the creation of robust, well-audited software that often benefits from rapid iteration and diverse contributions. Additionally, open-source projects allow users to gain insights into the development process, enhancing trust. This movement has also influenced business models, encouraging companies to adopt open-source solutions and contribute back to the community.