Selected track vs focused track

Sorry but I’m unclear as what the difference is between a “selected track” and a focused track”.
In the User Manual for Wavelab 10, describing the Track Pop-up Menu in the Audio Montage section (page 213) it says:
“ Copy Clips to Track Allows you to copy all selected clips from the selected track to the focused track”.

Set up 2 Tracks in a Montage.
In the Montage “select” Track 2 by clicking at the most left side
now make an selection in Track 1 by click dragging a area you like to copy
now paste this into Track 2…

regards S-EH