Terahertz (THz) refers to a frequency range in the electromagnetic spectrum that lies between microwave and infrared radiation, specifically from 0.1 to 10 THz. This range is significant for various applications, including imaging, communications, and spectroscopy, as it can penetrate materials like clothing and packaging without causing damage. The terahertz range is also important in scientific research, particularly in fields like material science and biomedical imaging. Researchers utilize terahertz waves to study the properties of materials and detect substances, making it a valuable tool for both industrial and medical applications.