In a contract of sale, the parties are the seller and the buyer while, in loan, the parties are the creditor and the debtor. In both, ownership over the thing sold or loaned (simple loan or mutuum) is transferred.

In sale, there is no obligation to return while, in loan (especially, simple loan), there is an obligation to return the same kind or quality. Therefore, if XXX bought a phone from YYY, YYY has no obligation to return. If AAA loaned 3,000 pesos from BBB, AAA has the obligation to return not exactly the same coins or bills but any coins or bills amounting to the same amount.

If a person, however, borrows a sum of money, and with it purchases in his own name a car, said purchaser would really be considered the buyer, and not the person who lent the money to him. Purchase in one’s own name with another’s money generally gives title to the purchaser named in the deed of sale. (Collector of Int. Rev. v. Favis, G.R. No. L-11551, May 30, 1960)