When a day trading order is placed by the trader, it will be sent to the exchange to be processed. The processing and the result of the processing are known as the following :
Order Execution
An order has been executed when it is accepted and processed by the exchange. This means that the order has been completed, but does not specify the details of how the order was completed.
Order Filled
The result of an order being executed is usually that the order is filled. This means that the order has been completed and all of the contracts have been traded. Sometimes, orders for multiple contracts will only be partially filled, which means that only some of the contracts in the order have been traded.

