Prior to the mid-19th century, most candles were made from tallow (a byproduct of beef-fat rendering). Nowadays, they are usually made from wax. Paraffin wax is the most common, but there are also candles made from gel, soya and beeswax.

A candle manufacturer is traditionally known as a chandler. Various devices have been invented to hold candles, from simple tabletop candle holders, to elaborate chandeliers.

The heat of the match used to light the candle melts and vaporizes a small amount of fuel. Once vaporized, the fuel combines with oxygen in the atmosphere to form a flame. This flame provides sufficient heat to keep the candle burning via a self-sustaining chain of events: the heat of the flame melts the top of the mass of solid fuel, the liquified fuel then moves upward through the wick via capillary action, and the liquified fuel is then vaporized to burn within the candle's flame.

The burning of the fuel takes place in several distinct regions (as evidenced by the various colors that can be seen within the candle's flame). Within the bluer regions, hydrogen is being separated from the fuel and burned to form water vapor. The brighter, yellower part of the flame is the remaining carbon being oxidized to form carbon dioxide.

As the mass of solid fuel is melted and consumed, the candle grows shorter. Portions of the wick that are not evaporating the liquid fuel are consumed in the flame, limiting the exposed length of the wick and keeping the temperature and rate of fuel consumption even. Some wicks require manual trimming with scissors or a wick trimmer for even burning.

History

Usage

Today, candles are used mainly for their aesthetic value and scent, particularly to set a soft, warm, or romantic ambiance, and for emergency lighting during electrical power failures. Scented candle are used in aromatherapy.

Religion

Candles are used in the religious ceremonies of many faiths.

Sikhism

The candle is used in Sikhism on Diwali, the festival of light.

Buddhism

Hinduism

In almost all Hindu homes, lamps are lit daily before the altar of the Lord. In some houses, the lamps, or candles, at dawn, and in some, twice a day - at dawn and dusk - and in a few, it is maintained continuously.

A diya, or clay lamp, is frequently used in Hindu celebrations and forms an integral part in many social rites. It is a strong symbol of enlightenment and prosperity.