# Cancellation

A task is a quantum of work that is cancelled or executes to completion. A cancelled task skips its method `execute()` if that method has not yet started. Otherwise cancellation has no direct effect on the task. A task can poll `task::is_cancelled()` to see if cancellation was requested after it started running.

The following table provides additional information on the members of this template class.
Member | Description
--- | ---
bool cancel_group_execution() | Requests cancellation of all tasks in its group and its subordinate groups. Returns: False if the task's group already received a cancellation request; true otherwise.
bool is_cancelled() const | Returns: True if task's group has received a cancellation request; false otherwise.

Parent topic: Task Scheduler

## See Also

task_group_context