Lighting the darkness
You'll find oil lamps burning in Hindu and Buddhist temples throughout India, Nepal and Tibet. In these cultures fire is a symbol of transformation, for Hindus the cremation after death is a transformative process. For a Buddhist the offering of light symbolises the Buddha dispelling the darkness of ignorance. Yak butter is traditionally used in Tibet - this is what gives the monasteries their characteristic smoky, buttery smell.
In Hindu temples coconut oil is used though cheaper vegetable oil seems to be used more and more in all places. Oil lamps, butter lamps are always photogenic, here a few photos from a trip to Nepal and Mustang in the summer of 2013. The last photo is of a butter lamp you can buy on our Buddha statues page.