You're reading the documentation for an older, but still supported, version of ROS 2. For information on the latest version, please have a look at Iron.
Many of the tf2 tutorials are available for both C++ and Python. The tutorials are streamlined to complete either the C++ track or the Python track. If you want to learn both C++ and Python, you should go through the tutorials once for C++ and once for Python.
If you have not yet created a workspace in which to complete the tutorials, follow this tutorial.
This tutorial will give you a good idea of what tf2 can do for you. It shows off some of the tf2 power in a multi-robot example using turtlesim. This also introduces using
Writing a static broadcaster (Python) (C++).
This tutorial teaches you how to broadcast static coordinate frames to tf2.
Writing a broadcaster (Python) (C++).
This tutorial teaches you how to broadcast the state of a robot to tf2.
Writing a listener (Python) (C++).
This tutorial teaches you how to use tf2 to get access to frame transformations.
Adding a frame (Python) (C++).
This tutorial teaches you how to add an extra fixed frame to tf2.
This tutorial teaches you to use the timeout in
lookup_transformfunction to wait for a transform to be available on the tf2 tree.
Traveling in time (Python) (C++).
This tutorial teaches you about advanced time travel features of tf2.
This tutorial teaches you basics of quaternion usage in ROS 2.
This tutorial teaches you about a systematic approach for debugging tf2 related problems.
Using sensor messages with tf2
Using stamped datatypes with tf2_ros::MessageFilter.
This tutorial teaches you how to use
tf2_ros::MessageFilterto process stamped datatypes.