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.
All these different names mean the same thing: TTY stands for teletypewriter, TDD stands for Telecommunication Devices for the Deaf and Text telephone means a phone that is enabled to send text over phone lines. All these terms are referring to the same device.