often transformers are required to supply several output voltages .
i believe these are called taps.
does each of these taps require a separate secondary coil or are the taps split off one larger secondary coil at the point where the required voltage is achieved .
In litteral terminology, multi-TAPPED is a single winding with taps to access more or less of the turns.
Transformers also frequently have multiple secondary windings.
A transformer with one winding, lets say its norminally 20V, and has a tap at 15V, you can get 15V, 20V or 5V from it.
A transformer with one 20V winding, and one 15V winding, can give you 15V, 20V, 5V or 35V.
Multi-tapped windings are generally a low cost and efficient way to get multiple output voltage options.
Frequently, transformers are made with taps on the primary side too, for example in my part of the world for 220 or 240 V operation.