1966 Lincoln Cent Question

There can be any kind of MD on a coin, and any kind of combination.

Machine Doubling. Note the affected areas are on the outside edge of the devices. That is area affected by machine movment during the strike. This slight movement affect the outside/inside areas of the devices. Depending on how loose the machine was. Sometimes there is a bounce that affects higher up on the devices. But this is caused by the machine. On a doubled die, it can be affected by Machine Doubling, but the actual hub doubling is on the die. This affects the centers of the devices, making the wider/taller. On your coin it MD on a normal die. While a doubled die can be affected with Machine Doubling, Machine Doubling never makes a doubled die. On a doubled die, will create a doubled die coin. Machine Doubling just alters the coins during the striking process. See the area affected, that is where the contour of the devices were altered by the machine. Just Machine Doubling.

This is a nice example of MD. the step-like and narrowed appearance of the devices give it away.