At their core, electromagnetic coils are quite simple: metal wire looped around a piece of shaped metal, typically a toroid or cylinder, which generates inductance when electrical current is introduced.Inductance is the property of such a coil to generate electromotive force when the current running through it experiences a change.
For such a simple concept, electromagnetic coils are a pervasive and incredibly important feature in all levels of electrical engineering. They’re employed most often in scenarios where electrical currents and electromagnetic fields directly interact — namely in electromagnets, sensor coils, inductors, and transformers.
