Due to the increasing demand for petroleum use as fuel, there has been a focus on the production of fuel that has a huge possibility for long-term energy sustainability. Synthetic gas (Syngas) is generated by means of a thermochemical technique known as gasification, which converts carbonaceous feedstocks (biomass, crude oil residuum, municipal waste, petroleum, and coal) to syngas. It contains carbon monoxide and hydrogen as the key elements of inflammable gas. It is widely used for gas lighting in coal gasification method before availability of electric lighting, gas turbine fuel, raw material for liquid fuels and the synthetic natural gas, and anode gas of solid oxide fuel cells. It is synthesized either through the gasification of plant-based biomass or pyrolysis of waste. This chapter will focus on the information, which has been rounded up over the last decades on syngas properties, sources, and production at a competitive advantage, as well as application and future technological advancement.