Contracts of sale involving goods are governed by Article 2 of the Uniform Commercial Code in most jurisdictions in the United States.
In some Muslim countries it is governed by sharia (Islamic law); however, many Muslim countries apply other law to contacts (e.g. the Egyptian Civil Code, based on the Napoleonic Code, which beyond its application in Egypt serves as the model for the civil codes of several other Arab states).
A contract of sale lays out the terms of a transaction of goods or services, identifying the goods sold, listing delivery instructions, inspection period, any warranties and details of payment.
According to the Civil Code of the Philippines Article 1458, the contract of sale has three stages: negotiation, perfection, and consummation.
[3] In the United States, according to the Uniform Commercial Code Article 2, the contract of sale can be formed in different ways: (1) offer and acceptance, where a sale begins with an offer and acceptance; (2) firm offers, where a merchant's written offer remains open for a specified time; and (3) battle of the forms, where conflicting terms in exchanged forms are resolved by the UCC.