Editing Austrian School (section)

===Opportunity Cost===
Opportunity cost is the cost of any activity measured in terms of the value of the next best alternative foregone (that is not chosen). It is the sacrifice related to the second-best choice available to someone, or a group, who has picked among several mutually exclusive choices.<br>Opportunity cost is a key concept in mainstream economics and has been described as expressing "the basic relationship between scarcity and choice". The notion of opportunity cost plays a crucial part in ensuring that resources are used efficiently.