Does anyone have an explanation of the Unity candle?

I wanted to put something about the meaning and symbolism in the program.

Thanks

This is what I put in our program:

The Unity Candle is a visual expression of the unity of people with each other and with God. The two smaller candles represent the lives of Cathy and Scott. Along with our parents, we will light the taller third candle with the two smaller ones to symbolize the bond of marriage, a bond that is so close we become one.