If you are new to investing and wanted to invest in the US, $S&P500 ETF(SPY)$ and $Vanguard S&P 500 ETF(VOO)$ will be the 2 ETFs that you can consider.They both track the S&P500 Index and are the largest in the ETF world. But are they the same? If you look closely there are 2 major differences.Expense Ratio: SPY charges 0.09% whereas VOO charges 0.03%Liquidity: SPY trades more than USD25 Billion shares daily versus VOO at USD1. 5 Billion shares. Wow! What a big difference in trading volume! SPY is the trading vehicle of choice of big institutions. They go for SPY because it is incredibly liquid and easy to trade. So the big question is which o