Move start date right
Click 
to move the start dates of the selected tasks or links to the right within the bar chart, ie to a later date. The start dates of the selected tasks or links move right by one of the current snapping time units each time you click the control. For example, if the current snapping time unit is weeks, the start dates of the selected tasks or links move a week later.
The finish dates of the selected tasks are not changed, so the tasks decrease in duration by one of the snapping time units each time you click the control.