The rainforest is a biome with lots of plants and animls that have adapted to survive there.
If a plant or an animal have adapted to survive in a certain place or in certain conditions, it means they can fit in**. **Think about the plants and animals in a desert. It if very dry and these plants and animals must adapt to live without a lot of water. The leaves of the plants will be thick and fleshy to store the water, the animals will come out at night when it is cooler etc.
Because it rains a lot in the rainforest and the plants can easily rot if they are always standing in too much water, the plants mostly have waxy surfaces and thick leaves so that the water will run off the plant quickly.
There are also plants like the orchards which are called an 'epiphyte'. They grow in trees to be higher up in the air, to get more sunlight and they get their food and water from the air around them.
You will also find some 'meat eating' plants that attract insects and they do not need the sun to photosynthesize (make their own food), because they will 'eat' a nice big fat bug.
Most of the nutrients are found in the top layer of the soil, so the roots of the plants will not grow to far down in the ground, in order to make sure it gets all the nutrients it needs.
Most of the animals in the forest live in the water or up in the trees. Only a few live on the forest floor.
There are quite a few humans living in this area and they live in 'harmony' with nature, which means they use the forest to feed them, supply shelter and give them medicine. If the trees are cut down and the area is being destroyed, it is called 'deforestation'.
There are companies that cut down the trees and sell it to other countries to make furniture. The machinery that they bring into the forest, also causes damage and the areas which are left without trees are now open for erosion and a lot of animals have lost their homes.
People also clear areas where they will use the land for farming and planting crops.
In many places mining is also taking place or roads and dams are built.