In Futures both buyer and seller agree to buy and sell the shares at a predetermined price on a specified date signed in the contract with obligation. On the date of agreement buyer will get the rights to buy and the seller gets rights to sell. But in call options, the buyer will get rights to buy option. In sell options, the buyer will get rights to sell. In both the cases the seller will get premium to sign the contract. It is up to the buyer to buy or sell.