Why is the concept of puts and calls applicable to options, but not to futures? Futures and options are similar, the key difference being that futures represent an obligation, whereas options represent a right. But this does not explain why we don't have, say, "put futures" and "call futures"?
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(a) it becomes clear that the former should not be used for futures when you consider that there can be options on futures and futures on options. So it would be really confusing to have to talk about a "put on a call position" or a "call position on a put".
(b) it makes sense that a verb (put/call) should be used to describe an option -- since it's an action that you might take some day -- and an adjective (long/short) should be used to describe a side of a futures contract -- since it is a position that you already have (even though it won't be made whole until the future).
The long/short description is so useful in describing an existing position that it is also used in most other markets. It is even used in options markets where you can buy 10 puts (you are now
long in puts) and then sell 12 puts (you are now
short in puts).