This is why they spend millions of dollars on exotic telecom equipment, just to shave off milliseconds from the latency.

So, for every share you trade on Robin Hood, they make a penny or a fraction of a penny.

Easy money. It’s even easier than taking candy from a baby. You never even knew that you were fleeced of that penny. At least a baby cries when you take his candy.

You as a retail investor or day trader cannot play that volume game with the HFTs, so there’s no point trying. But you can still do other strategies, like swing trading.