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Timeline and Gantt chart share a similar view of the tasks list and the calendar, however they are different in some points

• Task hierarchy in Timeline is Hierarchy: In the Timeline, the task hierarchy follows the Issue hierarchy in Jira (Initiatives → Epic → Issue → Sub-task) while . In contrast, the Gantt chart maintains uses a custom hierarchy based on the Work Breakdown Structure (WBS) numbernumbering.

• Advanced Features in Gantt Chart: The Gantt chart provides includes advanced Gantt features such as baseline tracking, critical path identification, inline task creation, drag&drop and the ability to update task hierarchy via drag and drop. Timeline doesn’t have those features.

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• These features are not available in the Timeline.

• Usage Options: You have the flexibility to use either the Timeline or the Gantt chart, or both, depending on your needs. This can be configured in the Feature settings

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The Complete Table Feature of Gantt and Timeline