Warren Edward Buffett (born August 30, 1930) is an American business magnate, investor and philanthropist. He is considered by some to be one of the most successful investors in the world. Buffett is the chairman, CEO and largest shareholder of Berkshire Hathaway, and is consistently ranked among the world's wealthiest people. He was ranked as the world's wealthiest person in 2008 and as the third wealthiest in 2015. In 2012 Time named Buffett one of the world's most influential people.

Buffett is often referred to as the "Wizard of Omaha" or "Oracle of Omaha," or the "Sage of Omaha," and is noted for his adherence to value investing and for his personal frugality despite his immense wealth. Buffett is a notable philanthropist, having pledged to give away 99 percent of his fortune to philanthropic causes, primarily via the Gates Foundation. On April 11, 2012, he was diagnosed with prostate cancer, for which he successfully completed treatment in September 2012. Buffett is also active in contributing to political causes, having endorsed Democratic candidate Hillary Clinton for president during the 2016 campaign season.

The extensive additional content in this second edition underscores topics of vital national or international significance. Some topics have been addressed in letters contained in previous editions by adding important new insights on recent developments; most consider subjects not previously addressed in the first edition. Topic highlights are the following:

? the passion for using independent directors in corporate governance contrasted with inherent limits and often sub-par performance of this cohort， especially in the mutual fund industry;

? the potential value of enhanced powers of audit committees on boards of directors in corporate governance;

? the high costs to investors and the capital markets of extensive reliance on and compensation of intermediaries and high volumes of trading activity;

? the proliferation of stock option compensation and excessive CEO pay (along with public debates concerning proper accounting treatment and political debates concerning standard setting);

? Berkshire?s shareholder-designated contribution program and related political controversy over the abortion issue that led to its termination;

? the explosion of derivative financial instruments and related perils and how Berkshire dealt with managing a sizable portfolio of them after buying Gen Re;

? the dramatic increase in foreign currency trading in the past five years along with the astonishing growth in the US trade deficit and evaluation of resulting national macroeconomic concerns;

? management succession at Berkshire Hathaway as Mr. Buffett ages， along with commentary on his philanthropic thinking in giving his entire fortune to charities coordinated by Bill and Melinda Gates; and

? the fairness and other matters concerning taxation of corporations， including Berkshire Hathaway.