When you put money into an index fund, that cash is then used to invest in all the companies that make up the particular index, which gives you a more diverse portfolio than if you were buying ...
Indexes have changed a lot over the past century. What was once state-of-the-art is now antiquated. The first indexes used information that was available, not what was best for building a portfolio.
An index fund is a fund that tracks a market index, such as the S&P 500. Index funds are designed to reflect the performance of a particular index, so their returns should run very close to those ...