Value chain is a high-level model of how businesses receive raw materials as input, add value to the raw materials through various processes, and sell finished products to customers. Value-chain analysis looks at every step a business goes through, from raw materials to the eventual end-user. The goal is to deliver maximum value for the least possible total cost.
Source: Value Chain Definition | Investopedia http://www.investopedia.com/terms/v/valuechain.asp#ixzz42Xb132SS