Tragedy of the commons

The tragedy of the commons is a term used to describe a problem that happens when everyone shares the same resource. It works like this: Imagine there is a big, shared field that lots of people use for grazing their animals. Everyone who has animals can use the field and it seems like a great idea to use the same space, but over time more and more people will bring animals to graze in the field. Eventually, too many animals in the same space will lead to overgrazing, which means that the grass in the field will not be able to grow back and will get used up. This means that the field is no longer a useful resource and everyone loses because the resource is used up. The tragedy of the commons is that when everybody wants to use the same resource, it often gets overused and can be made useless.