A turbo, short for turbocharger, is a device that is used in an internal combustion engine to increase its power output. It is a forced induction device that compresses the intake air, forcing more air into the engine, and allowing more fuel to be burned, producing more power for a given displacement. A turbocharger is powered by the kinetic energy of the exhaust gases, whereas a supercharger is mechanically powered (usually by a belt from the engines crankshaft) . A turbo works by forcing more air into the engine, with the amount of fuel being injected in increasing correspondingly, increasing the strength of the explosion and producing more power as a result.
Turbochargers were originally designed for use in aircraft and started to be fitted to cars in the 1960s. Today, the majority of modern petrol and diesel engines are turbocharged. A turbo is made up of two halves joined together by a shaft. On one side, hot exhaust gases spin the turbine that is connected to another turbine which sucks air in and compresses it into the engine. This compression is what gives the engine the extra power and efficiency because as more air can go in the combustion chamber, more fuel can be added for more power.
Advantages of turbochargers include extra power without sacrificing fuel efficiency. They are typically added to smaller engines to improve performance.