An Electromagnetic Bandgap (EBG) is a material or structure that can block certain frequencies of electromagnetic waves while allowing others to pass. This property is similar to how a semiconductor can control the flow of electrical current. EBGs are used in various applications, including antennas and microwave devices, to improve performance by reducing interference and enhancing signal quality. The concept of EBG is based on the periodic arrangement of materials, which creates a bandgap in the electromagnetic spectrum. This means that specific frequencies are reflected or absorbed, preventing them from propagating through the structure. EBGs are essential in designing advanced communication systems and improving the efficiency of wireless technologies.