This document defines acceptance under contract law and outlines the legal rules for a valid acceptance. It states that acceptance is the manifestation of assent by the offeree to the terms of the offer. It also discusses that for an acceptance to be valid, it must be made by the intended offeree, be absolute and unqualified, expressed in a usual and reasonable manner unless otherwise specified, communicated to the offeror, made within a reasonable time before the offer lapses or is revoked, come after the offer, and rejected offers cannot be accepted again without a new offer. Examples are provided to illustrate each of the legal rules.