Online repositories are digital storage spaces where data, documents, and resources can be stored, shared, and accessed over the internet. They are commonly used for academic research, software development, and collaborative projects. Examples include platforms like GitHub for code and Google Drive for general file storage. These repositories allow users to upload files, organize them into folders, and share them with others. They often include features like version control, which helps track changes made to documents or code, ensuring that users can revert to previous versions if needed.