What are the differences between a steam turbine and a steam engine?

turbine is driven, engine drives. in reality nothing, both use steam pressure to create a desired output. motion, turbine has 1 moving part that spins on it's axis. engine has many moving parts spinning an axis (crankshaft)
I really feel there is a huge difference in the way the two power generating sources work. The turbine uses steam at higher pressures and in my view less efficently than a closed piston power source does. lower pressures can be used in the closed piston type engine and levels of output can be changed by simply adding more cylinders or expanding the diameter of the piston,there are more moving parts than a turbine but if you figure in the steam adjust valves probally not that many more. I have never understood why an turbine is used as opposed to closed piston type engine. Thank you.
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A turbine opperates in a way similar to either a jet engine, or an old water-wheel. In either case, a steam turbine converst the thermal energy of the steam to rotary mechanical energy much more efficiently.
An engine (either a single set like a locomotive, or a block like a gas or diesel engine) uses both the pressure and the expansive poer of the steam to move a piston. The piston is connected to a rod which connects the backand forth motion of the piston to the rotary motion of the crankshaft.
A turbine is most fuel efficient in situations where full power is used most often, such as a powerplant, where the tubine spins a generator.
An engine is most efficient in low-speed, high torque applications, such as a pisotn set coupled to the drive wheels of an old steam locomotive.






















The steam produced for a steam engine drives a piston up and down or left to right, while the steam produced for a steam turbine turns the turbine itself.