Copolarization and cross polarization refer to the alignment of polarizing filters and their effects on light. Copolarization occurs when filters are aligned, allowing light to pass through with minimal change, while cross polarization happens when filters are at 90 degrees, blocking most light. Electromagnetic (EM) waves are polarized when the electric field vector is oriented in a specific direction, which is crucial for applications like TV transmission. For optimal reception, the receiving antenna must match the polarization of the transmitted signal. Understanding these concepts is essential for manipulating light and improving communication technologies.