Why is a candle made of wax?

Like a lamp and lantern, a candle is a type of source of light and heat, in which wax is used as a fuel. 

When a candle is lit, the wax melts and is vaporized and combusted, which in turn produces the heat and light.

Wax is a flammable, carbon-containing solid which becomes liquid when heated above room temperature. 

Almost any kind of oil can be changed into a wax.

Candle wax is made from many different types of sources (such as Beeswax, Soy wax, Coconut wax, Paraffin wax, Palm wax ), which possess different properties like, fragrance, durability, smoke-free flame, and stiffness.