A magnetic transformer magnetically couples the current in one wire to current in another. The effect is amplified using coils of wires and using a core of magnetic material (material with high permeability) to create greater magnetic flux density.
Inductors are components that can convert electrical energy into magnetic energy and store it. An inductor generally consists of a skeleton, a winding, a magnetic core, an iron core, a shielding case, and a package. Commonly used inductors are adjustable inductors and choke inductors.