The S&P 500: The Index You Need to Know
https://www.investopedia.com/articles/investing/090414/sp-500-index-you-need-know.asp
What Is the History of the S&P 500 Stock Index?
https://www.investopedia.com/ask/answers/041015/what-history-sp-500.asp
What Does the S&P 500 Index Measure and How Is It Calculated?
https://www.investopedia.com/ask/answers/040215/what-does-sp-500-index-measure-and-how-it-calculated.asp
How Is the Value of the S&P 500 Calculated?
https://www.investopedia.com/ask/answers/05/sp500calculation.asp
S&P 500 Average Return
https://www.investopedia.com/ask/answers/042415/what-average-annual-return-sp-500.asp
Does the S&P 500 Index Include Dividends?
https://www.investopedia.com/ask/answers/040915/does-sp-500-index-include-dividends.asp
How To Invest in the S&P 500
https://www.investopedia.com/ask/answers/how-can-i-buy-sp-500-fund/
Vanguard S&P 500 ETF
https://www.investopedia.com/articles/investing/121814/look-vanguards-sp-500-etf.asp
SPY ETF: What the SPDR S&P 500 ETF Trust Is and What It Holds
https://www.investopedia.com/articles/investing/122215/spy-spdr-sp-500-trust-etf.asp
Market Weight vs. Equal Weight S&P 500 ETFs: What's the Difference?
https://www.investopedia.com/articles/exchangetradedfunds/08/market-equal-weight.asp
The Top 25 Stocks in the S&P 500
https://www.investopedia.com/ask/answers/08/find-stocks-in-sp500.asp