Temporary tattoos are not permanent in nature and are easily removed with soap and water or oil-based creams and are intended to last a few days. Temporary tattoos are normally applied to the skin using water to transport the design to the surface of the skin. In some regions like India, the Middle East, North Africa and other Asian countries, temporary tattoo art forms are known as Mehndi / Mehendi.
Mehndi / Mehendi is applied generally on the hands and the feet. The designs made by Mehndi / Mehendi are intricate and beautiful and go on their own in a couple of days.
Henna is powdered and mixed with tea or coffee, lemon juice (so that the dye is released easily) and sugar to make a viscous paste which is then applied on the intended parts of the body. The more you leave the paste on the skin the more it will last. Usually, most of the designs last for about two weeks. Henna has tendency to fade in a fixed pattern. It fades from dark brown to light orange. The chief advantage of putting temporary tattoos like Henna or Mehndi is that you can get rid of them after a few days and again come up with a new pattern or style.
As Henna is herbal there is no threat to the skin. Black Henna, which is made by adding some chemical to the natural Henna, is very unhealthy and has been known to cause burns. According to tradition in the Asian countries in general and India in particular, Mehndi is applied onto the hands and feet of the brides and bridegrooms before wedding ceremonies.