-When looking for identical files,
-.B finddup
-by default associates a group ID to every content, and prints it along
-the file names.
+It compares files by first comparing their sizes, hence goes
+reasonably fast.
+
+When looking for identical files, \fBfinddup\fP associates by default
+a group ID to every content, and prints it along the file names.
+
+Note that
+.B finddup DIR
+is the same as
+.B finddup -i DIR DIR