"It is a minor operation that is normally carried out when you are still a little boy. The doctor cuts the top of the foreskin (prepuce) and leaves the end of the penis uncovered".
Peter Mayle.

"Mostly for religious reasons of Jewish families and Moslems. There are also other reasons to do this intervention, like avoiding that germs accumulate under the foreskin but keeping a regular and careful hygiene with the genitals zone, you will prevent this to happen".
Karen Gravelle.