Similar to the stocks and pillory, the pranger was connected from the neck via a chain, to a pair of leg restraints that were fastened around the offender's ankles. Often the chain was short so that the offender was placed in a very awkward, uncomfortable, semi-kneeling position.
There was also another type of pranger. The condemned was tied to a column that stood in the town center for public view. For more serious crimes he also could be flogged, marked by burned stigmata, or have his ears, nose or right hand cut off.
It is not a torture device, since it was only used for public humiliation as punishment, not for painful interrogation or other coercion.
In German the word was also used for the scolding bridle.