An intermediate in the combustion of carbon and hydrocarbons, carbon monoxide, is of special importance because it is a poisonous gas, but also economically useful for the production of syngas. Solid and heavy liquid fuels also undergo a great number of pyrolysis reactions that give more easily oxidized, gaseous fuels.
GM is short for General Motors. in text means Good Morning or means Good Move. Also means Genetically Modified.
It means Good game and is a way to show humility in defeat or victory. If you can't say GG or something nice, then dont. Saying stuff like BG or GG EZ can get you banned fast. Of course depending on the context it can be an insult.