An ‘at the money’ option is an option that would lead to zero cash flow to the holder if it were exercised immediately. An option on the index is at the money when the current index equals the strike price (i.e. spot price = strike price).
We simply attempt to be fearful when others are greedy, and to be greedy only when others are fearful.
The amount that must be deposited in the margin account at the time when a futures contract is first entered into is known as initial margin.