The vast majority of orders below have something to do with Stop Orders. Stop Orders should be thought of as "get me out" orders. Buy Stops are placed above the market and Sell Stops under the market. Under certain market conditions it is possible that your stop could be elected, but not filled because of prevailing market conditions. And yes, Stop Orders can be used to initiate new market positions.
A spread is an order to simultaneously buy and sell two different contract months of the same commodity(futures contract) or two different, but related commodities. This allows you to take advantage of the difference in prices, the spread in prices, from one month to the next of the same commodity.
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