# ROS Concepts

To learn:

* Nodes & Topics
* Publishers & Subscribers
* Services & Actions
* Launch Files & Parameters
* ROS File Structure & How to Write Packages

***

**Although on ROS1, the first 5 videos (\~1hr each) of this playlist is great to learn ROS Concepts. These concepts are very much the same in ROS2.**

{% embed url="<https://www.youtube.com/watch?v=Bcz3a-klKGk&list=PL868twsx7OjddCq3az74hu6pVsuJJzXvP&index=1>" %}

If you have followed my setup for ROS2 Humble, I recommend going through the Official ROS2 Humble Tutorials to have a hands-on for ROS2. Other distributions also have their own set of tutorials!

{% embed url="<https://docs.ros.org/en/humble/Tutorials.html>" %}

The tutorials are a collection of step-by-step instructions meant to steadily build skills in ROS 2.

The best way to approach the tutorials is to walk through them for the first time in order, as they build off of each other and are not meant to be comprehensive documentation.

* [Beginner: CLI tools](https://docs.ros.org/en/humble/Tutorials/Beginner-CLI-Tools.html)
  * [Configuring environment](https://docs.ros.org/en/humble/Tutorials/Beginner-CLI-Tools/Configuring-ROS2-Environment.html)
  * [Using `turtlesim`, `ros2`, and `rqt`](https://docs.ros.org/en/humble/Tutorials/Beginner-CLI-Tools/Introducing-Turtlesim/Introducing-Turtlesim.html)
  * [Understanding nodes](https://docs.ros.org/en/humble/Tutorials/Beginner-CLI-Tools/Understanding-ROS2-Nodes/Understanding-ROS2-Nodes.html)
  * [Understanding topics](https://docs.ros.org/en/humble/Tutorials/Beginner-CLI-Tools/Understanding-ROS2-Topics/Understanding-ROS2-Topics.html)
  * [Understanding services](https://docs.ros.org/en/humble/Tutorials/Beginner-CLI-Tools/Understanding-ROS2-Services/Understanding-ROS2-Services.html)
  * [Understanding parameters](https://docs.ros.org/en/humble/Tutorials/Beginner-CLI-Tools/Understanding-ROS2-Parameters/Understanding-ROS2-Parameters.html)
  * [Understanding actions](https://docs.ros.org/en/humble/Tutorials/Beginner-CLI-Tools/Understanding-ROS2-Actions/Understanding-ROS2-Actions.html)
  * [Using `rqt_console` to view logs](https://docs.ros.org/en/humble/Tutorials/Beginner-CLI-Tools/Using-Rqt-Console/Using-Rqt-Console.html)
  * [Launching nodes](https://docs.ros.org/en/humble/Tutorials/Beginner-CLI-Tools/Launching-Multiple-Nodes/Launching-Multiple-Nodes.html)
  * [Recording and playing back data](https://docs.ros.org/en/humble/Tutorials/Beginner-CLI-Tools/Recording-And-Playing-Back-Data/Recording-And-Playing-Back-Data.html)
* [Beginner: Client libraries](https://docs.ros.org/en/humble/Tutorials/Beginner-Client-Libraries.html)
  * [Using `colcon` to build packages](https://docs.ros.org/en/humble/Tutorials/Beginner-Client-Libraries/Colcon-Tutorial.html)
  * [Creating a workspace](https://docs.ros.org/en/humble/Tutorials/Beginner-Client-Libraries/Creating-A-Workspace/Creating-A-Workspace.html)
  * [Creating a package](https://docs.ros.org/en/humble/Tutorials/Beginner-Client-Libraries/Creating-Your-First-ROS2-Package.html)
  * [Writing a simple publisher and subscriber (C++)](https://docs.ros.org/en/humble/Tutorials/Beginner-Client-Libraries/Writing-A-Simple-Cpp-Publisher-And-Subscriber.html)
  * [Writing a simple publisher and subscriber (Python)](https://docs.ros.org/en/humble/Tutorials/Beginner-Client-Libraries/Writing-A-Simple-Py-Publisher-And-Subscriber.html)
  * [Writing a simple service and client (C++)](https://docs.ros.org/en/humble/Tutorials/Beginner-Client-Libraries/Writing-A-Simple-Cpp-Service-And-Client.html)
  * [Writing a simple service and client (Python)](https://docs.ros.org/en/humble/Tutorials/Beginner-Client-Libraries/Writing-A-Simple-Py-Service-And-Client.html)
  * [Creating custom msg and srv files](https://docs.ros.org/en/humble/Tutorials/Beginner-Client-Libraries/Custom-ROS2-Interfaces.html)
  * [Implementing custom interfaces](https://docs.ros.org/en/humble/Tutorials/Beginner-Client-Libraries/Single-Package-Define-And-Use-Interface.html)
  * [Using parameters in a class (C++)](https://docs.ros.org/en/humble/Tutorials/Beginner-Client-Libraries/Using-Parameters-In-A-Class-CPP.html)
  * [Using parameters in a class (Python)](https://docs.ros.org/en/humble/Tutorials/Beginner-Client-Libraries/Using-Parameters-In-A-Class-Python.html)
  * [Using `ros2doctor` to identify issues](https://docs.ros.org/en/humble/Tutorials/Beginner-Client-Libraries/Getting-Started-With-Ros2doctor.html)
  * [Creating and using plugins (C++)](https://docs.ros.org/en/humble/Tutorials/Beginner-Client-Libraries/Pluginlib.html)
* [Intermediate](https://docs.ros.org/en/humble/Tutorials/Intermediate.html)
  * [Managing Dependencies with rosdep](https://docs.ros.org/en/humble/Tutorials/Intermediate/Rosdep.html)
  * [Creating an action](https://docs.ros.org/en/humble/Tutorials/Intermediate/Creating-an-Action.html)
  * [Writing an action server and client (C++)](https://docs.ros.org/en/humble/Tutorials/Intermediate/Writing-an-Action-Server-Client/Cpp.html)
  * [Writing an action server and client (Python)](https://docs.ros.org/en/humble/Tutorials/Intermediate/Writing-an-Action-Server-Client/Py.html)
  * [Writing a Composable Node (C++)](https://docs.ros.org/en/humble/Tutorials/Intermediate/Writing-a-Composable-Node.html)
  * [Composing multiple nodes in a single process](https://docs.ros.org/en/humble/Tutorials/Intermediate/Composition.html)
  * [Using the Node Interfaces Template Class (C++)](https://docs.ros.org/en/humble/Tutorials/Intermediate/Using-Node-Interfaces-Template-Class.html)
  * [Monitoring for parameter changes (C++)](https://docs.ros.org/en/humble/Tutorials/Intermediate/Monitoring-For-Parameter-Changes-CPP.html)
  * [Launch](https://docs.ros.org/en/humble/Tutorials/Intermediate/Launch/Launch-Main.html)
  * [`tf2`](https://docs.ros.org/en/humble/Tutorials/Intermediate/Tf2/Tf2-Main.html)
  * [Testing](https://docs.ros.org/en/humble/Tutorials/Intermediate/Testing/Testing-Main.html)
  * [URDF](https://docs.ros.org/en/humble/Tutorials/Intermediate/URDF/URDF-Main.html)
  * [RViz](https://docs.ros.org/en/humble/Tutorials/Intermediate/RViz/RViz-Main.html)


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