Magnetic cores are materials that enhance the magnetic field in electrical devices, such as transformers and inductors. They are typically made from ferromagnetic materials, which can easily become magnetized. By concentrating the magnetic field, these cores improve the efficiency of energy transfer and reduce energy losses in electrical circuits. These cores come in various shapes and sizes, including toroidal and E-shaped designs, depending on their application. The choice of core material, such as ferrite or silicon steel, affects the performance and frequency response of the device. Properly designed magnetic cores are essential for the effective operation of many electronic systems.