Every plant or animal has an address - its habitat. The habitat provides all that the plant or animal needs. A frog's address - shady pool, the bottom of the garden - provides shelter, food and some safety. A frog would not live in a desert - which would not provide it with any of this.

Life at that address will be tough. The plants at any address will be eaten by animals, because only plants can make their own food. They do that using the power of the Sun. Plants are producers. Animals could lie in the Sun all day and still be hungry - so many animals eat plants instead. They are consumers. Other animals let these herbivores eat the plants and then they eat the herbivores in turn. They are consumers too - the carnivores.

To help us understand the different plants and animals around us, we give them all names. It's obvious that many of them are very alike - they are in families. So cats, lions and tigers are all alike - in the cat family. A branching key that asks you questions about a plant or animal - 'Is it legless? Does it wriggle after you and give you a nasty bite?' can help you identify them.