Why use oil lamps?

How to create an oil lamp? - Oil lamps are made out of small earthen cups filled with ghee or oil and ignited using the small thread dipped in the oil.

Reasons

1. In olden days when no electricity was invented, lighting oil lamps provided light in the night and in dark homes and temples.
2. Fire had been an uncontrollable power in the pre-spark era of humans. Once man had understood the rules of controlling fire, this ritual of lighting a lamp came into place to remind every individual of power of fire.
3. In vedic times, fire was kept alive in every household in some form and carried with oneself while migrating to new locations. Later the presence of fire in the household or a religious building was ensured by an oil lamp. [[http://en.wikipedia.org/wiki/Oil_lamp#Importance_of_Oil_Lamps_in_India]]