How does electromagnetism produce light?

James Clerk Maxwell unified electricity and magnetism in the 1860s and showed that changing electric and magnetic fields can travel through space as waves. That prediction led to the modern understanding of light as part of the electromagnetic spectrum. When electrons accelerate, such as in an antenna, atom, or hot object, they can emit electromagnetic radiation. Different frequencies produce radio waves, visible light, X-rays, and more. Visible light is only a tiny slice of the full spectrum, but it is the range our eyes evolved to detect.