"Trading positions are provided in the common nomenclature of long (will happen) and short (will not happen). The trading unit is a contract with a notional settlement value, typically $10, and the contract may trade in range of 0-100. If the event specified in a given contract occurs, the contract settles at 100 points; otherwise, the contract settles at 0. Thus, the current price of the contract can be imputed as the market's global opinion of the probability that the specified event will occur."
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its like a stock market there is a bid and ask for everything
if it wins than the contract expires at 100....if it loses it expires at 0
they are prediction markets
kinda like how the financial markets have prediction markets in which money is traded in to predict if the fed will cut interest rates or not....and many other things relating to the economy
