Whether lighting a cigarette, lighting a candle, or anything in-between, lighters are a common item that people frequently use. The mechanics behind it, however, usually go unnoticed. The simple fact is that a lighter does not spark magic; a complicated system occurs within the lighter's plastic cover.
Modern lighters are mostly disposable with an outer plastic shell. They run on butane gas, an easily-flammable gas that, when released by opening the valve, creates the flame. The valve is opened by rolling the sparkwheel and pushing down on the button located at the very top of the lighter.
Steel lighters are still available but are no longer as prominent as they were many years ago. These lighters are refillable and will last a long time, incorporating the same basic lighting mechanism.
The classic fire-making method of flint and steel is used, in miniature form. The flint is what supplies the material to create the spark. It's made of ferrocerium, a man-made metallic material that ignites spark when scraped against steel. The flint is kept in place by the flint spring. It applies pressure to the flint and pushes it against the sparkwheel; when the flint and the sparkwheel come into contact, a flame ignites.
To maintain that flame, butane is released when the valve is opened. A fork spring is connected to the sparkwheel, and an item known as a jet is connected to the spring. When the wheel is turned, the jet rises to allow butane to steadily flow out. As soon as the sparkwheel and button are released, the jet lowers and the valve closes, stopping the flame.
These components are all necessary in order for the spark to initiate and continue until let up. Without a spark, the flame could not exist. Without the butane gas, the flame would not hold. Because not all lighters can be made perfectly, some flames are larger and some are smaller; this is because of the length of the fork spring and the amount of gas that essentially gets out.
This is the classic and most-popular method of lighters used today. A new method has risen, however, incorporating piezoelectricity. Here, a quartz crystal replaces the flint (still kept in place by a spring) and the sparkwheel is replaced with a button and tiny hammer. When the button is pushed at the top of the lighter, the hammer (held against the quartz) rises to a certain level and releases directly into the quartz, creating a burst of electricity.
Early lighters used a wick and copper wire to start a flame. The wick is soaked in fuel and connected to a copper wire, which is then connected to the flint. When the sparkwheel is pressed, a spark ignites from the flint, which ignites the fuel-soaked wick and copper wire to sustain a flame. Classic Zippo lighters are made this way, but most current lighters use the above methods. Zippos can be refilled with butane gas that can be bought at any gas station or auto/hardware store.
The mechanics within a lighter are pretty complicated, making it all the more incredible that a flame can be created with the spin of a wheel. Lighters, in their most simplest form, have been around for centuries. With the invention of pocket and disposable lighters, they continue to be one of the most useful and widely-used products on the market.