Shulchan Arukh, Yoreh De'ah 180/שולחן ערוך·יורה דעה ק״פ

1 The Prohibition of tattooing, and balding for the dead. Contains 12 sections. Incised writing is defined as cutting one's flesh and filling the place of cutting with kohl [following the emendation of Biur HaGra YD 180.2] or ink or any other dye that leaves a mark.

2If he does this on his friend's flesh, the one to whom it was done is exempt unless he aided in the matter.

3One is permitted to place ash on their wound.

4One who marks their slave lest they escape is exempt (But it seems that, in the first place, it is forbidden).

5One who cuts their flesh is not culpable unless they are doing it for their deceased, or for idolatry. However, for their deceased, one is culpable whether one did it manually or with a tool, while for idolatry one is only culpable if it was with a tool.

6Scratching and cutting for the deceased is prohibited, even outside the presence of the deceased [But it is permitted to do so because of another source of pain. (B"Y based on Tur)]

7Some say that specifically cutting is forbidden but hitting with the hand on the flesh until blood flows is permitted, and some forbid it.

8One who makes five cuts for one deceased person, or one cut for five deceased people has five culpabilities.

9Balding is is defined as removing the hairs from one's head over a death, from any place on the head, whether by hand or with a potion, and at its minimum size, a bean-size area of one's head must be visibly empty of hair. And some say: two hairs. And some say that a prohibition even extends to one hair.

10If one created one bald area for five deceased people, they are only culpable once, but if they created five bald areas for one deceased person, they are culpable for each one.

11One who creates a bald spot on a friend's head, or cuts a friend's flesh, while the friend supports it: if they both do so intentionally, they both receive lashes. If one did so by accident and one intentionally, the intentional one receives lashes.

12Women are also cautioned against balding. [Comment of Rema: And how much more so against cutting (Tur). And it is right to caution them not to remove their hair by the deceased person, so that they do not come to violation of the prohibition on balding (Tur citing Yerushalmi) and likewise with cutting.]