According to the Encyclopaedia Britannica, a major benefit of methane is as the main component of natural gas, a major source of fuel and synthetic materials for humanity. Natural gas is used as a fuel for home heating, power plants and some vehicles, particularly municipal bus systems. It is also used to manufacture methanol, formaldehyde and chloroform.
Methane is naturally an odorless and colorless gas which is less dense than the major gases in air. It is the simplest hydrocarbon, with one carbon atom bound to four hydrogen atoms in each molecule. It constitutes about 75 percent of natural gas, with the next simplest hydrocarbon, ethane, which has two carbon atoms and six hydrogen atoms, constituting another 15 percent. The University of Wisconsin notes that most fuel applications, sulfur compounds are added to natural gas to give it a scent and make it more detectable. Concentrations about 5 percent are explosive in air, and high levels can also displace oxygen, causing asphyxiation in any people present. Methane is not toxic, however.
Methane is often manufactured deliberately, although in natural gas it is mined, found trapped in various rock strata. It is also produced in large quantities by anaerobic bacteria when digesting cellulose, such as in marshes or in the guts of various animals, most notably cows and termites.