The electric chair and cotton candy were both invented by dentists - Dr. Albert Southwick and Dr. William Morrison, respectively.

Saturday became part of the weekend in the early 19th century, when British factory owners gave workers Saturday afternoons off to drink, allowing Sunday for recovery before work on Monday. Before that, only Sunday was a day off.

There’s a species of jellyfish that can technically live forever. Turritopsis dohrnii can revert its cells to an earlier stage of life, effectively restarting its life cycle — making it biologically immortal.

Belly buttons can harbour thousands of bacterial species. In one study, a participant’s belly button contained bacteria found only in Japanese soil - despite never visiting the country. Another hosted microbes typically found in deep-sea thermal vents.

The average person in the world is a 28-year-old right-handed Chinese male who speaks Mandarin, according to statistics released by National Geographic.

The most expensive cheese in the world is Pule cheese. It's made in Serbia from donkey milk and priced at around $600 per pound (about $1,320 per kilogram).

Around 80% of plane crashes occur during the first three minutes after takeoff or the final eight minutes before landing.