manual/include/align-spot-regions.html

<p>
  Aligning regions (sometimes called "spotting") means moving one or more
  regions based on a defined location, which in Ardour is always the
  <a href="/ardours-interface/the-edit-point-control/">edit point</a>. An 
  alignment operation moves the region(s) so that some part of the region
  is positioned at the edit point. Available alignment commands include:
</p>
<dl class="wide-table">
  <dt>Align Region starts <kbd class="mod14">a</kbd></dt>
  <dd>Selected region(s) are moved so that their start is located at the current edit point</dd>
  <dt>Align Region ends <kbd class="mod2">a</kbd></dt>
  <dd>Selected region(s) are moved so that the end is located at the current edit point</dd>
  <dt>Align Region sync points <kbd>Shift-a</kbd></dt>
  <dd>Selected region(s) are moved so that their sync point is located at the current edit point</dd>
  <dt>Align Region starts relative <kbd class="mod4">a</kbd></dt>
  <dd>Selected region(s) are moved so that the start of the earliest region is located at the current edit point, and all others maintain their relative position relative to that region</dd>
</dl>