A commonly used tool for source code management is Git. Git provides version control capabilities, allowing developers to track changes in their codebase, collaborate with team members, and manage multiple development branches effectively. It enables rollback of changes if necessary, facilitating easier bug fixes and feature implementation. Git integrates with various platforms, such as GitHub and GitLab, to offer additional functionalities like issue tracking and continuous integration. Its distributed nature makes it highly efficient and scalable for projects of all sizes.