Having confusion over nodes’ communication methods: by topics and by service.

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I have confusion over nodes’ communication methods. So far what I’ve understood is that there is two ways which are by topics and by service. Please correct me if I am not right.

1- In both methods, massages are used for sending and receiving information.

2- In communication by topic only one node can publish to a topic but several nodes can subscribe to that topic.

3- The communication by service is the way that only two nodes can send and receive information by messages.

Now, If all of the above statements are correct, my question is whether it is possible that a node subscribes/publishs to a topic and at the same time it communicates to another node(in another package) using service method? If it is, how can I do that?

Thanks for considering my question.