Ansible provides a robust command-line interface, which provides users with the ability to run Ansible playbooks, simulate the execution of Ansible playbooks, run ad hoc commands, and much more. In the Ansible galaxy (more to come on that specific pun later in the book), there are two specific types of Ansible commands that can be run. The ansible command allows users to run ad hoc commands, whereas the ansible-playbook command allows the user to execute a set of Ansible playbook instructions against the targeted infrastructure.
This is ambiguous within the documentation, Ansible and Ansible-playbook appear to be symlinks but there are some reports of different functionality between the two. More research is needed before final drafting to ensure accuracy of information reported. For now, there will be a section for Ansible and Ansible-playbook...