Index Funds是什麼？

Index Funds - What You Don't Know -- GuruFocus.com: "John Bogle, the founder of Vanguard Group, started the first index fund in 1975 after Burton Malkiel popularized the efficient market theory (EMT) and commented 'It is time the public can [buy an index].' The EMT basically says the stock price reflects all the best information currently available (even though it may be incorrect) about the company. Now that you know what EMT is, you can skip all 522 pages of Burton Malkiel's A Random Walk Down Wall Street."