Options are traded in units of contracts. Typically, One contract unit is equal to 100 shares (corporate actions may result in 1 option not being equal to 100 shares).
For example, in the case of option contract AAPL 170314 140.00C, its quoted price is $2, meaning the price (premium) of this contract is $2 * 100 = $200. Upon exercise, you will receive 100 shares of AAPL.