the.com/electromagnetic
Electricity and magnetism, secretly the same force wearing two different costumes.
means Describing the unified phenomenon where moving electric charges create magnetic fields, and vice versa, including light itself.
from From Greek elektron (amber, which sparks when rubbed) plus magnetis (stone of Magnesia, the region whose ore tugged iron); fused after Oersted's 1820 compass twitched near a wire.
Same thingLight, radio, and X-rays are all this.
Maxwell's giftFour equations described it all by 1865.
Speed limitIts waves travel at lightspeed, because they are light.