Fossil Fuels-Coal, Oil and Natural gas The age of this source of energies goes back to the beginning of life on earth. Hundred million years ago, abundance of huge trees and leafy plant in swamps and algae in seas and stagnant pools were the dominant form of life in our planet. These planets by sinking to the button of swamps and oceans, formed layers of spongy material which under pressure of rocks piled upon them in the later periods, squeezed and depending to circumstances changed to one the mentioned forms of fuels. Hear we should mention that the main deposits of fossil fuels are from carboniferous period.    Coal Coal in its black rocky form, is made up of mainly carbon, plus some hydrogen, oxygen, nitrogen and sulphide. Amongst three main types of anthracite coal is the hardest one and rich in carbon content. Bituminous is the third type. Peat, a precursor to coal is found in many parts of the world, used as an energy source. Chinese were the fist ones that used the coal as a source of energy. Energy produced from coal was used to smelt copper as early as 3000 years ago. They found the burning property of coals. Coals are found in many parts of the world. Various methods are used to dig out the coal. Some of the mines are deep in ground, requiring digging under the ground bring them out, using the elevators, trains and miners on the other hand, strip mines needs huge steam shovels, cut the top layers reaching the coal. The mined out coal is shipped by trains and boats. By pulverizing the coal and mixing with water, pasty matter called slurry is produced. Such a product could be transferred along the pipelines miles away. This slurry material could be used readily in power plants and factories.    Oil or Petroleum A second type of fossil fuel has probably diatoms origin. Diatoms are sea creatures in the size of pin head. In a similar behavior like plants they have the capability of changing sun energy to stored energy. By the time of dying, they sank to the sea floor, where they are buried under sediment and rocks. By squeezing underneath, the energy in their bodies is saved. Pressure and heat changes this energy in a long time to oil. Ancient people used it in a crude form. Using this material as asphalt (pitch) and as a medicine or heating and light goes back to thousands years ago among Sumerians, Assyrians. They found oil in seeps which were places on the ground having leaked up oils. The name of asphalt is derived from a place near the Dead Sea, having lumps of crud oil taken to the shores from under water beds. As well in other parts of the world were found pockets of petroleum, use for different purposes. As the demand for energy has increased rapidly, the low price of oil in compare to other energy sources has replaced their using. As a result, using the white oil or oil from distilled coal is no more generally accepted? The method of drilling a well for extracting oil was in mid 18th century in Pennsylvania. Nowadays the same method is used worldwide to bring the under ground to surface. Oil and natural gas found between layers of porous rocks. The shifts and movements of earth cause forming the rocky folds. Generally, the oil fields are drilled by oil companies. Reaching to oil and gas, they pump them out by different means. Oil produced in this way will be transferred mostly by pipelines and ships. Most of the world oil comes from Middle East. Alaska, North Sea, California is among the other places, having a large quantity of oil. Oil in crude form is useless and must be changed to refined form. The shipped oil is stored in large tanks. Oil refineries change and split crude oil to many types of products and by products. Looking around you may find many things produced from oil. Even clothes, plastic bottles and farming fertilizers have an oil origin. Thousands of products come from oil that makes it our most valuable necessity in our daily life. As a fuel you may find its use in gasoline for cars, diesel fuel, aircraft fuel, home heating oil, power plants for making electricity. All these come from what we call crude oil. As you see a considerable portion of this material is used in transportation section. Later we will disuses more in this regard. Natural gas was discovered by ancient Iranians Thousands years ago. Eternal fire in temples were most likely burned this kind of fuel. Other parts of Middle East especially Baku region has a vast fields of natural gas. By being lighter than air, natural gas is mainly of a gas known as methane. It is a simple chemical, made up of one carbon and four hydrogen atoms. This gas has a high flammability. Natural gas is found wherever petroleum exists. Pipelines are the main medium transferring the pumped out gas. To prevent explosion caused by accumulated gas, purposely chemicals are added to this odorless, unseen gas, giving alarm of its presence. The strong odor of these gases leakage from pipes and cylinders. Thereby, any smell similar to rotten eggs must consider a gas leakage. Any spark in an enclosed gas filled area could be catastrophic. So, Opening the doors and not turning on the lighting switches or fire are a must. You better leave the area immediately, call the fire station.    Saving the Energy As the reservoir of fossils is limited, any wasteful consuming of it must be prevented. By conserving this valuable fuel, maybe we find a solution for its replacement in future.