Millimeter waves are a type of electromagnetic radiation with wavelengths ranging from 1 millimeter to 10 millimeters, corresponding to frequencies between 30 GHz and 300 GHz. They are situated between microwave and infrared waves in the electromagnetic spectrum. Due to their short wavelengths, millimeter waves can carry large amounts of data, making them useful for high-speed wireless communication. These waves are increasingly used in various applications, including 5G technology, satellite communications, and radar systems. Their ability to penetrate fog and rain makes them effective for certain types of imaging and sensing. However, they can be absorbed by atmospheric gases, which limits their range.