Signs and Wonders: 50 Intriguing Symbolism and Facts to Astonish You

The @ symbol was selected for the first electronic mail because the developer sought a rarely used symbol.

Purple butterfly stickers on incubators indicate infants with a deceased twin.

The Red Hand is Ulster's symbol due to a myth involving a boat race to determine a king. A contender, about to lose, severed his hand (staining it red) and threw it ashore to claim victory.

Sunflowers (lanyards, buttons, etc.) are a universal sign for those who have hidden disabilities, and there's a massive network that supports this signage.

The Peace Symbol represents the flag semaphores for ‘N’ (flags held at 5 and 7 o’clock positions) and ‘D’ (flags held at 12 and 6 o’clock) and stands for Nuclear Disarmament.

Dunce caps were originally a sign of high intelligence and wisdom. Philosopher and theologian John Duns Scotus was a proponent of pointy hats as a way to funnel knowledge to the mind, and his followers, called Dunsmen, wore them. By the 1500s, the Dunsmen fell out of favor as "behind the times".

The lightbulb is the universal symbol for a new idea because of Felix the Cat cartoons.

Most hotel rooms in Arab countries have a sticker or sign that shows which way Mecca is, so Muslim guests know which way to pray.

There is an "official" Unicode anger symbol. It's 💢, which represents veins on your forehead when your blood pressure rises.

The Hammer of Thor is an approved religious symbol for veteran gravestones in the US, and two soldiers have such headstones.