history - quick recap
of energy, frequency, and vibration. in terms of frequency / vibration... electric field; magnetic field cosmic rays gamma rays X-ray ultra-violet Visible spectrum infra-red microwave radio Human eyes see just 0.0035% of the known electromagnetic (EM) spectrum. This sliver is called visible light and spans wavelengths between 380 and 780 nanometers. The remaining 99.99%—which includes radio waves, microwaves, infrared, ultraviolet, X-rays, and gamma rays—remains entirely invisible to us. Infrared (IR): We perceive the longer waves of infrared radiation as heat on our skin, though we cannot see the light itself. Radio & Microwaves: These have even longer wavelengths and lower energy; while we don't naturally feel them, technologies like Wi-Fi, radios, and cell phones operate within these bands. UV, X-Rays, & Gamma Rays: These have wavelengths shorter than visible light and carry high amounts of energy. We cannot physically sense them until they cause cellular damage (l...