ROS 2 is designed as an everything-included framework for robotics. It generally maintains alignment with the architecture and philosophy of the original ROS.
Carried-over from ROS to ROS 2 was its topic naming convention, and the inclusion of the 'Parameter' system for every application.
These two details work together to create large numbers of 'parameter' topics, even in systems that do not use the ROS 2 parameter feature.
Here's how that happens:
