How does money grow? Super Simple Answer; Interest. Simple interest, compound interest, indexed interest all combine to make one thing; Growth.

 There are thousands of types of funds and thousands of ways that they make money, but the easiest way for you to see is check the numbers.

Play around, see what you get.   Had you invested $10,000.00 in 2009 in an S&P 500 indexed fund, left it there and not touched it. that 10K would be worth $73,922.96 today. Remember this is past performance, and you  can't bank on it, but, it is a fairly good indicator.