Natural gas is a kind of combustible gas mixture of fossile origin occurring in the earth’s crust. It is derivative of petroleum. It is number two in list of importance as a fuel, after crude petroleum. A great portion of the natural gas comprise of hydrocarbon component called Methane gas (CH4) in 70-90%. Other components are; ethane (C2H6), propane (C3H8), buthane (C4H10) gases. It also contains trace amounts of carbondioxide (CO2), nitrogene (N2), helium (He) and hyrogenesuphur (H2S).

The hydrocarbon compounds that comprise the natural gas are also the components of the petroleum in underground. In the past the natural gas was considered as unuseful pollutant and was discarded by burning it in the petroleum installation. Nowadays, it is utilized in our homes and in the industry as a rather valuable and strategical energy source.

The natural is produced in all the continents of the world excluding Antartics. The largest producer in the world is the Commonwealth of the Independent States. USA, Canada, Holland and Iran are also important natural gas producing countries.

The most efficient and least costly method of transporting the natural gas is to utilize the pipelines. In the USA there are approximately 3,2 million kms of natural gas pipeline the most of which were laid down during the World War II. Apart from this, the natural gas can be transported in liquidified form inside the compressed tanks. The requirement of maintaining high pressure and low temperatures in the transportation of the liquidities natural gas (LNG), makes this method of transportation less efficient compared to the method of the pipelines.

Since the natural gas is found in combination with the petroleum, it exists in the areas of petroleum fields. There is a continuously developing natural gas industry. Today the largest natural gas deposit of the world is in the northern region of Qatar. It is estimated to contain 25 trillion m3 gas.