Henna is used in creating paint for the purpose of decorating the skin. This is mainly popular in Indian weddings. Henna can be used in dying the hair a gingery-red colour.
A form of 'henna' called black henna when applied to the body can cause scarring and permanent damage to the skin if applied. Natural henna does not harm the skin.
Henna is usually applied as a paste or gel.
Henna paste for decorating the skin. (Source unknown. Product of Ranikone)