Warrants belong to options, call warrants are call options, put warrants are put options, and the buyer of options needs to pay the seller a premium, which is the current transaction price of warrants. The buyer has rights but no obligations, and the seller has obligations but no rights, so the buyer's income is infinite, while the seller's income (premium charged) is limited and the loss is infinite. Futures is simply a contract, and the rights and obligations of buyers and sellers are symmetrical with risk and return.