What is a Steam Engine and how has it developed through the ages?
A steam engine is a device that converts the potential energy that exists as pressure in steam, and converts that to mechanical force. Early examples were the steam locomotive trains, and steamships that relied on these steam engines for movement. The Industrial Revolution came about primarily because of the steam engine. The thirty seconds or so required to develop pressure made steam less favoured for automobiles, which are generally powered by internal combustion engines.
The first steam device was invented by Hero of Alexandria, a Greek, before 300BC, but never utilized as anything other than a toy. While designs had been created by various people in the meanwhile, the first practical steam engine was patented by James Watt, a Scottish inventor, in 1769. Steam engines are of various types but most are reciprocal piston or turbine devices.
The strength of the steam engine for modern purposes is in its ability to convert raw heat into mechanical work. Unlike the internal combustion engine, the steam engine is not particular about the source of heat. Also, modern steam engines burn fuel cleanly and efficiently, with relatively little pollution.