Fundamentally, it has to do with buying great companies actions, but they are poorly evaluated due to factors inherent in the stock market, such as the unpredictability and irrationality in the short term.
It is common that you reduce the market value of stock for less than its real value. But a shrewd investor who knows the concepts and strategies of value investing, know how to take advantage of this momentary incoherence.
The Valu Investing concept was introduced by Benjamin Graham in his book Security Analysis, published in 1934. Since then, investors know that the stock market should be treated with caution and with long-term follow bias successfully Graham's teachings.