Option spread

Options spreads are the basic building blocks of many options trading strategies. A spread position is entered by buying and selling equal number of options of the same class on the same underlying security but with different strike prices and/or expiration dates. The three main classes of spreads are the horizontal spread, the vertical spread and the diagonal spread. They are grouped by the relationships between the strike price and expiration dates of the options involved.
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The trading of options of the same class at the same time in order to profit from changes in the size of the spread between different options.