1) The world's first credit card was introduced in 1950 by Diners Club.

2) The national animal of Australia is the kangaroo.

3) In Aztec mythology, Quetzalcoatl is a prominent deity often depicted as a feathered serpent. He is associated with creation, fertility, and wind, and is considered a cultural hero and patron of priests and rulers. The arrival of Spanish conquistadors was interpreted by some as the return of Quetzalcoatl.

4) The concept of gravity was famously described by Sir Isaac Newton after an apple fell on his head.