Traditional oil lamps are mostly used by people in Indian subcontinent especially by Hindu religioun people. They also go by the name of Diyo or Diya batti. It is made from a clay in which a cotton thread is placed that is dipped inside a ghee or oil so that it can last more. In every temples here in our country, the oil lamp can be seen especially during night even though it is also seen in morning time. However, I have also noticed the use of this lamp in Buddhist stupa multiple times. I don't know what's the significance of lighting the lamp but it is said that by lighting the oil lamp, we can beat the darkness or evil forces and enlighten ourselves. These lamps are considered to be very environment friendly as well creating enchanting atmosphere with good smell and good vibes.