# Order Types Orders are instructions to buy or sell assets at specified conditions. They define what, when, and how trades should execute on the exchange. Ethereal supports a diverse range of order types and configurations: * **Market:** Executes immediately against resting liquidity; any unfilled size is canceled. * **Limit:** Placed at a specific price and stays on the order book until filled or cancelled. Filled at selected limit price or better * **GTD (Good-Till-Date):** Stays live until the chosen expiry or when the order fills. * **IOC (Immediate-or-Cancel):** Fills what it can instantly, cancels the rest. * **FOK (Fill-or-Kill):** Must fill in full at once or cancel entirely. * **Stop orders** * **Stop Market:** A market order that is executed at the best market price when mark price reaches selected market price * **Stop Limit:** A limit order that is only executed at selected limit price after mark price reaches selected trigger price. * **Market close orders:** Automatically-size to fully close your current position, canceling any resting or untriggered orders before closing automatically. * **Reduce-only orders:** Ensures the order can only decrease your current open position size. * **Limit**: Limit reduce-only orders automatically adjust if a subsequent order reduces your current position * **Trigger orders (OTO / OCO groups):** * **OTO (One-Triggers-Other):** First order fills first; then linked order activates once first has concluded. * **OCO (One-Cancels-Other):** Linked orders live together. Filling one cancels the others. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.ethereal.trade/trading/perpetual-futures/order-types.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.