Final answer:
The electromagnetic spectrum includes visible and invisible light. Visible light is a small range of frequencies detected by the human eye, while invisible light refers to other forms of electromagnetic radiation.
Step-by-step explanation:
The electromagnetic spectrum encompasses all forms of electromagnetic radiation, including visible and invisible light. Visible light is a small range of frequencies within the spectrum that can be detected by the human eye, typically ranging from 400 to 700 nanometers (nm) in wavelength. Invisible light refers to the other forms of electromagnetic radiation outside the visible range, such as infrared, ultraviolet, X-rays, and radio waves.