In Buddhist ceremony, you can usually see light of candle or light of lamp. What does it mean when being used in Buddhism? For the answer of this question, you can see the nature of light of a candle. "Candle" is being used here as at those former times, candles are very common compared to other source of light.
When you see the light of a candle, what cross in your mind? The candle burns itself and light will come out and shine brightly around it. From this, you can see that "Offering of Candle in Buddhism" has a deep meaning. It symbolizes that we should put others in front of ourselves. Thinking others first. That also means to remove our egoist mind. Buddhas and Bodhisattvas are truly like the candles that burning themselves (willing to sacrifice) for all beings' sake. Buddhas and Bodhisattvas are the Light that guides all sentient beings in darkness.
When a candle is lit up, it can light up other candles. That means when we put others first, then other people probably will follow our examples, thus creating a bright wonderful world. Here's a Mandarin song which describes the meaning of Candle Light in Buddhism. This song is called 一盏灯 (A Lamp)