Mr. Market is an allegory created by investor Benjamin Graham. Since its introduction in Graham's 1949 book The Intelligent Investor, it has been cited many times to explain that the stock market tends to fluctuate, and that it is usually best to ignore these fluctuations when determining whether to buy or sell stocks. Graham instead believes that it is important to focus on whether the stock valuation of a company is reasonable after calculating its value through fundamental analysis. Warren Buffett has been quoted numerous times on Graham's 1949 book The Intelligent Investor. Chapter eight covers Mr. Market and Warren Buffett thinks that this is the best part of the book.  Buffett described it as "by far the best book on investing ever written"