production.ini            # inventory file for production stage
development.ini           # inventory file for development stage
test.ini                  # inventory file for test stage

group_vars/
    all                   # variables under this directory belongs all the groups
    webservers            # here we assign variables to webservers groups
    postgresql            # here we assign variables to postgresql groups
plays
    ansible.cfg           # Ansible.cfg file that holds all ansible config
    webservers.yml        # playbook for webserver tier
    postgresql.yml        # playbook for postgresql tier

roles/
    requirements.yml      # All the infromation about the roles
    external              # All the roles that are in git or ansible galaxy
                          # This directory is in ignored by git and all the roles in the 
                          # requirements.yml will be downloaded into this directory
    internal              # All the roles that are not public