Stop order

In MetaTrader 5 a Buy Stop is placed above the current Ask and deals when the Ask is at or above the stop. A Sell Stop is placed below the current Bid and deals when the Bid is at or below the stop. The help page describes these as orders placed in anticipation of the move continuing. That is a description of how the order is used, not a prediction. CME's stop does not rest on the book until a trade prints at the trigger. It then becomes a market order, or a limit order if it is a stop-limit. A stop can fill some distance from the trigger when the next available price is worse. It does not cap the loss at the trigger price.