# cvs > Concurrent Versions System, a revision control system. > More information: . - Create a new repository (requires the `CVSROOT` environment variable to be set externally): `cvs -d {{path/to/repository}} init` - Add a project to the repository: `cvs import -m "{{message}}" {{project_name}} {{version}} {{vendor}}` - Checkout a project: `cvs checkout {{project_name}}` - Show changes made to files: `cvs diff {{path/to/file}}` - Add a file: `cvs add {{path/to/file}}` - Commit a file: `cvs commit -m "{{message}}" {{path/to/file}}` - Update the working directory from the remote repository: `cvs update`