| A | B |
| Consideration | Exchange of benefits and detriments by the parties to an agreement. |
| Revocation | The taking back of an offer by the offeror. |
| Void | A contract that amounts to nothing and has no legal effect |
| Bilateral | A contract that contains a promise by both parties. |
| Genuine agreement | If a valid offer is met with a valid acceptance. |
| Law | Any agreement enforceable at law |
| Implied Contract | A contract that comes about from the actions of the parties. |
| Capacity | The legal ability to enter a contract. |
| Rejection | A refusal of an offer by the offeree that brings the offer to an end. |
| Counteroffer | Acceptance that changes the terms of the original offer and terminates the offer. |
| Acceptance | Unqualified willingness to go along with an offer. |
| Offer | Proposal by one party to another party to enter into a contract. |
| Express Contract | A contract stated in words; it may be oral or written. |
| Unilateral Contract | Contains a promise by only one person to do something, if and when the other person performs some act. |
| Invitation to negotiate | Advertisements in newspapers, catalogs, magazines, price tags, signs in store windows and on counters, and prices marked on merchandise. |
| Mirror Image Rule | The acceptance must not change the terms of the original offer in any way. |