A task is a planned action to support a specific goal or project.
A task can be defined and documented in reasonably predictable ways which apparently do not require a new project or subproject. (However, tasks can turn into projects.)
Official plans often assign responsibility for tasks to be performed by, or delegated by, specific agents.
Depending on context, agents may potentially complete an assigned task by directly performing the tasks, by delegating them, or by otherwise satisfactorily supporting the completion of the task.
function: a function can be defined as one or more potentially recurring tasks.