Git is a widely-used version control system that allows developers to track changes in source code during software development. It manages and records changes to files, facilitates collaboration by enabling multiple developers to work on the same project simultaneously, and helps in maintaining a history of modifications. Git supports branching and merging, which allows developers to work on features or fixes in isolation and then integrate their work into the main codebase. Its distributed nature means each user has a full copy of the repository, enhancing data security and enabling offline work. Tools like GitHub and GitLab provide hosting services for Git repositories, offering additional collaboration and project management features.