How communication goes between ROS, Gazebo, and Rviz?

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Hi

I am not new to ROS practically, but there is something I need to understand,

How communication goes between ROS, Gazebo, and Rviz? I mean using simulated robot not a real one.

Can Rviz communicate directly with Gazebo or through ROS?

I have searched for diagram to explain and visualize the relationship between the three, and how the messages goes between them, but I could not find one? I think diagram will help me alot, could you please refer or recommend one?

Thanks in advance,