The following article is excerpted from West's Encyclopedia of American Law . A promise, arising by operation of law, that something that is sold will be merchantable and fit for the purpose for which it is sold.
Sales contracts are frequently oral, unwritten agreements.
The purchase of items like a candy bar hardly seems worth the trouble of drafting an agreement spelling out the buyer's expectation that the candy bar will be fresh and edible. Implied warranties protect the buyer whether or not a written sales contract exists. An implied warranty of merchantability is an unwritten and unspoken guarantee to the buyer that goods purchased conform to ordinary standards of care and that they are of the same average grade, quality, and value as similar goods sold under similar circumstances. In other words, merchantable goods are goods fit for the ordinary purposes for which they are to be used. Thus, a buyer can sue a seller for breaching the implied warranty by selling goods unfit for their ordinary purpose.