What do four dot tattoos on the hand signify?

A four-dot tattoo on the hand, especially on the knuckles, traditionally signifies that the wearer of the tattoo has been in prison for four years. Tattoos consisting of three or five dots are also associated with criminals and prison.

The three-dot tattoo is an indication of Latino gang membership and stands for "mi vida loca," which means "my crazy life." The five-dot tattoo consists of four dots forming a square, with the fifth dot sitting in the middle. This tattoo indicates the four walls of a prison cell, with the single dot in the middle representing the prisoner. Both these tattoos typically appear on the back of the hand between the thumb and index fingers.