Astronaut Neil Armstrong first stepped on the moon with his left foot. See more

The thumbnail grows the slowest; the middle nail grows the fastest. See more

Zero point energy is a source of energy which is released when atoms stop moving, at -273 Celcius. See more

Hummingbirds are the only birds that can fly backwards. See more

Leonardo Da Vinci invented the scissors. See more

The longest one-syllable words in the English language are "strengths" and "screeched". See more

Al Capone's business card said he was a used furniture dealer. See more

A cat has 32 muscles in each ear. See more

In rural areas, there are more insects in 1 square mile than there are humans on earth. See more