It is one of the basic principles taught to students studying economics. Introduced by Lord Alfred Marshall, it forms a crux in the micro-economic level often reflected in routine, day-to-day life.

Andrew Bloomenthal has 20+ years of editorial experience as a financial journalist and as a financial services marketing writer. Erika Rasure is globally-recognized as a leading consumer economics ...

Sean Ross is a strategic adviser at 1031x.com, Investopedia contributor, and the founder and manager of Free Lances Ltd. Somer G. Anderson is CPA, doctor of accounting, and an accounting and finance ...