What is a limit order vs a market order — when should I use each?

Use a market order when you want immediate execution and the stock is highly liquid (like an S&P 500 ETF) — price precision matters less. Use a limit order when trading less liquid stocks, entering at a specific price point, or if a small price difference is meaningful. During volatile markets or for thinly traded securities, always use limit orders to avoid paying much more (or receiving much less) than expected.