Electromagnetic shielding is a technique used to block or reduce electromagnetic fields from penetrating a specific area. This is achieved by using materials that can absorb or reflect electromagnetic waves, such as metals like copper or aluminum. Shielding is essential in various applications, including electronics, telecommunications, and medical devices, to prevent interference and ensure proper functioning. The effectiveness of electromagnetic shielding is measured in decibels (dB), indicating how much the shield reduces the electromagnetic field. Proper design and material selection are crucial for achieving optimal shielding performance, especially in sensitive environments like hospitals or data centers.