manual/include/selecting-tracks.html

<p>
  Tracks are <dfn>selected</dfn> by clicking on the Track header at the left
  of the Editor window. You can select multiple tracks with <kbd class="mod1
  mouse">Left</kbd> clicks, or a range of consecutive tracks with <kbd
  class="mod3 mouse">Left</kbd>.
</p>
<p>
  By default, <dfn>selecting regions</dfn> has no impact on
  <dfn>track selection</dfn>.
  You can select a track, then select a region in another track
  (or vice versa) and both selections will co-exist happily.
  Operations that are applied to tracks will use the track selection,
  and those that apply to regions will use the region selection.
  Similarly, deselecting a region will not deselect the track it
  is in (if that track was selected).
</p>
<p>
  In some workflows, and particularly if you have experience with
  other <abbr title="Digital Audio Workstation">DAW</abbr>s, this
  is not the most comfortable way to work. You may prefer to work
  in a style where selecting a region will also select the track
  that the region is in. Similarly, when the last selected region
  in a track is deselected, the track will also become unselected.
</p>
<p>
  To control this behaviour, set <kbd class="menu">Edit &gt;
  Preferences &gt; Editor &gt; Link selection of regions and tracks</kbd>.
</p>