A contract is a legally bining exchange of promises or agreement between parties that the law will enforce. Contract law is based on the Latin phrase pacta sunt servanda (pacts must be kept).Breach of contract is recognised by the law and remedies can be provided. Almost everyone makes contracts every day. Sometimes written contracts are required, such as when buying a house. However, most contracts can be and are made orally, like buying a law textbook, or a coffee at a shop. Contract law can be classified, as is habitual in civil law systems, as part of a general law of obligations (along with tort, unjust enrichment or restitution).