By default, certain tasks will be run against the control node (that's your Ansible server) or against your managed nodes (the target systems). For example:
There are different ways to modify this behavior. The following can be used to invoke a module on the control node (that's your Ansible server).
Or, it you can set -hosts: localhost in your playbook to run the playbook against the control node.
--- - hosts: localhost tasks: - debug: msg: Hello World ...