The term forest can be defined in many different ways.

According to one Finnish definition, a forest is "a region where a squirrel can jump from one tree to another." Overall, a forest can be defined as an area where trees are present.

The forest is a whole that consists of interactions between living organisms and their non-living environment. This means that the forest is an ecosystem.

There are no forests in some parts of the world. For example, you cannot find a forest in regions like the Canadian tundra or the Arabian desert.

The reason for the lack of forests in the tundra is the cold temperature, whereas in deserts forest growth is hindered by drought.

In Northern Europe, there is a lot of water for plants to use. The temperature is also sufficient for accomodating plant growth. This is why there are a lot of forests in Northern Europe.

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