Often in front of the main temple there is a candle stand and an incense burner. Before praying one lights a candle and/or incense stick.
The offering of candles is to shine a light on the darkness of the world and create the correct path towards Buddha. Candles are an age old traditional part of Buddhist rituals. In conjunction with incense and flowers, candles are placed in front of Buddhist shrines or statues and images of the Buddha as a mark of respect. They are often accompanied by offerings of food and drink. The light of the burning candle flame represents the light of the Buddha’s teachings. As I learnt when travelling in Japan, you must not light the candle with another candle that has been lit by somebody else.
On the other hand, incense cleanses oneself and the space around, while also inviting Buddha to make himself welcome. Usually, you would light the candle first, then light the incense from the candle. A standard practice is to bow to Buddha with your palms together, then (leaving one hand in the palms-together position) light one end of the incense.