Click the "folder set" button at upper right. Create a new folderset, rename it if you like.  Click a checkbox to add some folders to scan (My Pictures is a good start).  Click "done". Click (re)Scan Folderset. The file list on the left side are the images in the folder path shown at the top of the program.  When the scan is finished you can click on any file to see the 40 closest matches on the righthand file list.    Mousewheel is enabled. Delete/Rename/Move/Describe files with right-mouseclick menu, or Del/Alt-R/Alt-M/Alt-D.   Multiple files are selectable with shift-click and ctrl-click. Find duplicates with "Next Duplicates" button.  Restart the search at the beginning by entering 0.   Exact matches are found with distance threshold 0.  Notice the distance between left and right images displayed in red at lower right. Launch your favorite file viewer by double clicking on either image. Double-click on any file in the righthand closest-matches-list to switch to that file's directory on the lefthand file browser.