As one of the most respected portfolio managers in the world and chairman of Berkshire Hathaway, Warren Buffett continues to motivate value investors around the world. His investment formula is comprised of two parts -- knowing and understanding the company's business and execution capabilities in detail, and purchasing at a reasonable valuation.

Warren Buffett is known for his investing success, generating market-beating returns over the long run. As chairman, he's helped Berkshire Hathaway deliver a compounded annual gain of more than 19% over 58 years -- that's as the S&P 500 posted a compounded increase of about 10% during that period.

Warren Buffett is known for advising investors to stay within their circle of competence, which means not buying or even considering businesses or industries that the investor cannot understand. He has also said that he missed out on many big opportunities in the technology sector because he didn’t truly understand the industry dynamics.

Warren Buffett's Berkshire Hathaway owns one of the world's most closely watched stock portfolios. It holds stakes in 46 stocks and exchange-traded funds that are worth $296.8 bil