Managing a Project: Editing Project Plans in Timeline View

Plans can be modified utilizing drag and drop functionality in a project's timeline view. Here's how:

Open the project whose schedule you wish to modify, open the View menu, and select the Timeline (Gantt Chart) option from the dropdown menu.
The Timeline View of the project opens. To drag and drop a task or phase, mouse over that task/phase until the standard cursor arrow becomes a four pointed arrow.
Drag and drop the task or phase either forward (into the future) or backward (earlier than its current date). Note that the updated date for that task is displayed as changes are being made. Once the task or phase has been dropped in its new location, click Save to commit changes or Cancel to discard them.
To adjust the duration of a task in timeline view, mouse over the right side of the task to be adjusted until a two-sided arrow appears. This indicates that the task can now have its duration increased or decreased by dragging to change the task length. Again, a panel will appear displaying the dates and duration associated with this task as the changes are being made. Click Save to commit changes or Cancel to discard them.
When tasks that lie on the Critical Path are updated, the other tasks in this project will not automatically be changed to address the new shifts to dates/duration. To update the rest of the project plan to reflect the updated dates/durations, click on the View menu, and select Critical Path from the dropdown menu.
The Critical Path view of the project opens, displaying the other tasks that have been impacted by the change(s). Click the Update button to view a listing of proposed updates to the project plan.
The Update Timeline dialogue opens, displaying all tasks impacted and the proposed changes to the schedule. Click Save to apply proposed changes.
The project plan updates. Return to the Timeline View to see these updates reflected in the project plan.