A legal document, usually in writing, giving details of a formal legally binding agreement, between two or more different people or groups. To be legally binding it must contain certain elements: it must contain an offer made by one party and accepted in its entirety by the other, it must include some form of consideration whether it be money, goods or services, and it must be properly signed by all parties to it, and dated.

A contract in which all elements of a contract are specifically stated (offer, acceptance and consideration), and the terms are set out, as compared with an implied contract in which the existence of the contract is assumed by the circumstances.

A period immediately after the deadline for the performance of an obligation during which a late fee or penalty, or other action would have been taken as a result of failing to meet the deadline, is waived provided that the obligation is satisfied during the grace period. Grace periods can range from a couple of minutes to a number of days or longer, depending on the context, and can apply in various situations, such as complying with a legal obligation by a specified deadline.