Near-infrared (NIR) refers to a portion of the electromagnetic spectrum with wavelengths ranging from about 750 nanometers to 1,400 nanometers. This range is just beyond the visible light spectrum, making it invisible to the human eye. NIR is commonly used in various applications, including remote sensing, medical imaging, and spectroscopy. NIR light can penetrate materials like skin and vegetation, allowing for the analysis of their properties without direct contact. For instance, in agriculture, NIR technology helps assess plant health by measuring how plants reflect light. This information can guide farmers in optimizing crop management and improving yields.