In this chapter, we introduced ROS and practiced with simple examples in order to help you understand the architecture of ROS. The top-level entity is the workspace, which is an isolated environment for building and running your software.
The workspace is constituted by ROS packages, that is, premade pieces of software that provide specific functionalities to integrate into your robot. Following this, catkin is the tool used to build the software each time you include new packages in your workspace.
The node is the basic entity in ROS and holds the functional pieces of code that make the robot work. A collection of related nodes providing specific functionalities constitute a ROS package. roscore, the process that runs the master node, is the one that allows each node to be capable of finding others by subscribing to the published topics. roscore also manages the database...