Different types of environments exist all over our planet. When you are in the middle of one it is often easy to see what makes it special. Around the edges it becomes more difficult to recognize. It starts to blend with the environment it borders. These edges are places of great species diversity.
Scientists divide environments into smaller groups to better explore them and explain them. For example, forests are one of the major types of environment. But, there are different types of forests in different parts of the world. For example, rainforests are one forest type. Even rainforests are divided into tropical rainforests and temperate rainforests.