Types of stop orders
Stop order Stop-limit order
Offers execution protection only, not price Offers price protection only, not execution
Must be manually canceled and re-entered Must be manually canceled and re-entered
Held on the book at the execution venue Held on the book at the execution venue
No costs if not executed No costs if not executed
Tends to work well in slowly declining markets Tends to work well in slowly declining markets
Generally does not work well in halted or gapping markets Generally does not work well in halted or gapping markets

Source: Schwab Center for Financial Research