Select by Location window

This window is shown from the Selection Assistant menu.
The Select By Location tool (also known as Select by Master Path) is used for marking files which duplicate the ones in your selected path. For example, you select the path you want to keep (eg D:\Photo), and the files in D:\Data\Temp which duplicate those in D:\Photo will be marked.
Select by Location window

Path Name

1. Path Name
The 'master' path name

Mark button

2. Mark button
Begin the marking operation.

Include Subfolders of this path check

3. Include Subfolders of this path check
This includes all subfolders of this path.

Select Folder button

4. Select Folder button
Brings up a folder selection dialog box.