accelerate: DEPRECATED, set to True to use accelerate connection plugin.
accelerate_ipv6: DEPRECATED, set to True to force accelerate plugin to use ipv6 for it's connection.
accelerate_port: DEPRECATED, set to override default port use for accelerate connection.
action: The 'action' to execute for a task, it normally translates into a C(module) or action plugin.
args: DEPRECATED, A secondary way to add arguments into a task, it takes a dictionary in which keys map to options and values .. well you get it.
always: List of tasks, in a block, that execute no matter if there is an error in the block or not.
always_run: DEPRECATED, forces a task to run even in check mode, use check_mode directive instead.
any_errors_fatal: Force any un-handled task errors on any host to propagate to all hosts and end the play.
async: Run a task asyncronouslly if the C(action) supports this.
become: Boolean that controls if privilege escalation is used or not on Task execution.
become_flags: A string of flag(s) to pass to the privilege escalation program when ``become`` is True.
become_method: Which method of privilege escalation to use. i.e. sudo/su/etc.
become_user: User that you 'become' after using privilege escalation, the remote/login user must have permissions to become this user.
block: List of tasks in a block.
changed_when: Conditional expression that overrides the task's normal 'changed' status.
check_mode: A boolean that controls if a task is executed in 'check' mode
connection: Allows you to change the connection plugin used for tasks to execute on the target.
delay: Number of seconds to delay between retries, this setting only makes sense when used with 'until'.
delegate_facts: Boolean that allows you to apply facts to delegated host instead of inventory_hostname.
delegate_to: Host to execute task instead of the target (inventory_hostname), connection vars from the delegated host will also be used for the task.
environment: A dictionary that gets converted into environment vars to be provided for the task upon execution.
fact_path: Set the fact path option for the fact gathering plugin controlled by ``gather_facts``.
failed_when: Conditional expression that overrides the task's normal 'failed' status.
force_handlers: Will force notified handler execution for hosts even if they failed during the play, it will not trigger if the play itself fails.
gather_facts: A boolean that controls if the play will automatically run the 'setup' task to gather facts for the hosts.
gather_subset: Allows you to pass subset options to the  fact gathering plugin controlled by ``gather_facts``.
gather_timeout: Allows you to set the timeout for the fact gathering plugin controlled by ``gather_facts``.
handlers: A section with tasks that are treated as handlers, these won't get executed normally, only when notified. After each section of tasks is complete.
hosts: A list of groups, hosts or host pattern that translates into a list of hosts that are the play's target.
ignore_errors: Boolean that allows you to ignore task failures and continue with play. It does not affect connection errors.
loop_control: Several keys here allow you to modify/set loop behaviour in a task see http://docs.ansible.com/ansible/latest/playbooks_loops.html#loop-control for details.
max_fail_percentage: can be used to abort the run after a given percentage of hosts in the current batch has failed.
name: It's a name, works mostly for documentation, in the case of tasks/handlers it can be an identifier.
no_log: Boolean that controls information disclosure.
notify: list of handlers to notify when the task returns a 'changed=True' status.
order: Controls the sorting of hosts as they are used for executing the play. Possible values are inventory (default), sorted, reverse_sorted, reverse_inventory and shuffle.
poll: Sets the polling interval in seconds for async tasks (default 10s).
port: Used to override the default port used in a connection.
post_tasks: A list of tasks to execute after the ``tasks`` section.
pre_tasks: A list of tasks to execute before ``roles``.
remote_user: User used to log into the target via the connection plugin. AKA login user.
register: Name of variable that will contain task status and module return data.
rescue: List of tasks in a block that run if there is a task error in the main ``block`` list.
retries: Number of retries before giving up in a 'until' loop, this setting is ignored on it's own.
roles: List of roles to be imported into the play
run_once: Boolean that will bypass the host loop, forcing the task to execute on the first host available and will also apply any facts to all active hosts.
serial: Defines the 'batch' of hosts to execute the current play until the end.
strategy: Allows you to choose the connection plugin to use for the play.
tags: Tags applied to the task or included tasks, this allows selecting subsets of tasks from the command line.
tasks: Main list of tasks to execute in the play, they run after ``roles`` and before ``post_tasks``.
until: This keyword implies a 'retry loop' that will go on until the condition supplied here is met or we hit the retry limit.
vars: Dictionary/map of variables
vars_files: List of files that contain vars to include in the play.
vars_prompt: list of variables to prompt for.
vault_password: Secret used to decrypt vaulted files or variables.
when: Conditional expression, determines if an iteration of a task is run or not.