### Comment:
Can you explain this to me?

### REPLY:
1. You wanted to buy shares of company X at $100 and you put in a market order 
  
 2. Robinhood sells your info to high frequency traders, said traders buy the share at 100 and sells back to you for $100.5. 
  
 3. Robinhood gets a cut of that 50 cents profit.

### END.