The ROS filesystem

The ROS filesystem mainly covers how ROS files are organized on the disk. The following are the main terms that we have to understand when working with the ROS filesystem:

• Packages: ROS packages are the inpidual unit of the ROS software framework. A ROS package may contain source code, third-party libraries, configuration files, and so on. ROS packages can be reused and shared.
• Package manifests: The manifests (package.xml) file will have all the details of the packages, including the name, description, license, and, more importantly, the dependencies of the package.
• Message (msg) types: Message descriptions are stored in the msg folder in a package. ROS messages are data structures for sending data through ROS's message-passing system. Message definitions are stored in a file with the .msg extension.
• Service (srv) types: Service descriptions are stored in the srv folder with the .srv extension. The srv file defines the request and response data structure for the service in ROS.