Opportunity cost

Opportunity cost or economic opportunity loss is the value of the next best alternative forgone as the result of making a decision.[1] Opportunity cost analysis is an important part of a company's decision-making processes but is not treated as an actual cost in any financial statement.The next best thing that a person can engage in is referred to as the opportunity cost of doing the best thing and ignoring the next best thing to be done.

Opportunity cost is a key concept in economics because it implies the choice between desirable, yet mutually exclusive results. It is a calculating factor used in mixed markets which favour social change in favour of purely individualistic economics. It has been described as expressing "the basic relationship between scarcity and choice."[2] The notion of opportunity cost plays a crucial part in ensuring that scarce resources are used efficiently.[3] Thus, opportunity costs are not restricted to monetary or financial costs: the real cost of output forgone, lost time, swag, pleasure or any other benefit that provides utility should also be considered opportunity costs.

(From Wikipedia，http://en.wikipedia.org/wiki/Opportunity_cost)

[1] McConnell, Campbell; Stanley L. Brue (2005). Microeconomics: Principles, Problems, and Policies. McGraw-Hill Professional. pp. 27. ISBN 0072875615.
[2] James M. Buchanan (1987). "opportunity cost," The New Palgrave: A Dictionary of Economics, v. 3, pp. 718-21.
[3] The Economist's definition of Opportunity Cost

The Chinese definition of opportunity cost is:
机会成本是指由于选择一种方案而放弃另一方案的收益,又称择机代价或替换成本.机会成本区别于一般概念的会计成本含义,广义上指一种资源如果具有多种用途,那么资源用于其他方面可能获得的最大边际方面的机会.

简单举一例。现有A公司出月薪1000要求你去上班，B公司以月薪1500请你上班。 如果你选择去A公司，你的机会成本为1500 如果选择去B公司，则机会成本降至1000,这就是最通俗你解释。(来自百度知道：http://zhidao.baidu.com/question/14638209.html)