Submillimeter waves are a type of electromagnetic radiation with wavelengths ranging from 0.1 to 1 millimeter. They fall between microwave and infrared radiation on the electromagnetic spectrum. These waves are used in various applications, including astronomy, where they help scientists study celestial objects and phenomena. In technology, submillimeter waves are utilized in imaging systems and communication devices. They can penetrate materials like fog and dust, making them useful for remote sensing and surveillance. Researchers also explore their potential in medical imaging and security screening, highlighting their versatility in both scientific and practical fields.