Insects outnumber humans by 250,000 to 1.
There have been more than 1,000,000 different kinds of insects discovered in the world. In the U.K. there are more than 21,000 different kinds.
The body of an insect has three main parts; the head, thorax and abdomen.
All insects have six legs.
The skeleton of an insect is on the outside of its body. It's called an 'exoskeleton'.
The eyes of insects are made up of lots of tiny lenses called 'facets'. This sort of eye is called a 'compound eye'. Some insects have 100 facets on each eye. Dragonflies can have up to 28,000.
Insect blood is normally green, although it can vary in different species. The blood does not need to carry oxygen to its cells, and so it does not contain haemoglobin, which is what makes human blood red in colour.
Insects breath through tiny holes in their abdomen called 'spiracles'.
The heart of an insect is like a flexible tube sealed at one end, running along the back.