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docs/subtasks.markdown

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+Subtasks
+========
+
+Subtasks are useful to split the work of a task.
+
+Each subtask:
+
+- Can be assigned to a project member
+- Have 3 different statuses: **Todo**, **In progress**, **Done**
+- Have time tracking information: **time spent** and **time estimated**
+- Be ordered by position
+
+Creating subtasks
+-----------------
+
+From the task view, on left sidebar click on **Add a subtask**:
+
+![Add a subtask](http://kanboard.net/screenshots/documentation/add-subtask.png)
+
+You can also add quickly a subtask by entering only the title:
+
+![Add a subtask from the task view](http://kanboard.net/screenshots/documentation/add-subtask-shortcut.png)
+
+Change subtask status
+---------------------
+
+When you click on the subtask title the status change:
+
+![Subtask in progress](http://kanboard.net/screenshots/documentation/subtask-status-inprogress.png)
+
+The icon before the title is updated according to the status.
+
+![Subtask done](http://kanboard.net/screenshots/documentation/subtask-status-done.png)
+
+Note: When the task is closed, all subtasks are changed to the status **Done**.
+
+Subtask timer
+-------------
+
+Each time a subtask is in progress, the timer is also started. The timer can be started and stopped at any time.
+
+The timer records the time spent on the subtask automatically. You can also change manually the value of the time spent field when you edit a subtask.
+
+The time calculated is rounded to the nearest quarter. This information is recorded in a separate table.
+
+The task time spent is updated automatically according to the sum of all subtasks time spent.
+