A stop order rests unseen until a trade occurs at or through its stop price (at or above it for a buy stop, at or below it for a sell stop); it then becomes a market order. A stop-limit order becomes a limit order at its stated limit price instead.
firm.exchsim: the fall caused by one market sell of 3 000 shares into a ladder of 500 shares a cent, against the number of 800-share sell stops placed a cent apart from 99.95 down. Data: mx_ordertypes.stop_cascade.