The core of a transformer is laminated to reduce energy losses caused by eddy currents. Eddy currents are circulating currents induced in the solid core by the alternating magnetic field, which create heat and waste energy. Laminating the core—i.e., constructing it from thin, insulated sheets of electrical steel—restricts these currents to smaller paths within each lamination. This increases the resistance to eddy currents, greatly reducing their magnitude, thereby minimizing heat generation and improving the transformer's efficiency. Additionally, laminations are coated to electrically insulate them from each other, preventing short circuits between layers. Other benefits of a laminated core include reduced core weight and prevention of rusting, along with maintaining high magnetic permeability to efficiently channel the magnetic flux between the transformer's coils. In summary, laminating the transformer core helps prevent eddy current losses, enhances efficiency, reduces heat, and improves overall performance by using thin, insulated steel sheets rather than a solid iron core.