As well as having unique fingerprints, humans also have unique tongue prints.
Red blood cells carry oxygen around the body. They are created inside the bone marrow of your bones.
Natural gas doesn't have an odour, strong smells are added to it by humans so it can be detected when there are leaks.
The Earth isn't perfectly round, it is slightly flattened at the north and south poles.
Mt Everest is the highest mountain on earth, its peak reaches 8,848 metres (29029 feet) above sea level.
Stretching out to an impressive length of 6696 kilometres (4160 miles) long, the Nile River is the longest river on earth.
The world's largest desert is the Sahara. It covers about one third of Africa!
English physicist Sir Tim Berners-Lee is regarded as having invented the World Wide Web in 1989.
The average life span for a dog is around 10 to 14 years.
Dogs have a remarkable sense of smell, they are capable of differentiating odors in concentrations nearly 100 million times lower than humans can.