| A | B |
| gratuitous | the law does not enforce free agreements |
| preexisting duty | legal obligation to do something |
| benefit | something a person was not previously entitled to receive |
| detriment | a loss suffered from an agreement |
| forbearance | not doing something you have legal right to do |
| bargained for exchange | promise made in return for another promise, act or promise not to act. |
| unconscionable | agreement or contract that is completely out of line |
| release | agreement to sign if not suing someone |
| accord and satisfaction | contract is discharged when one party to agreement accepts performance from other party which is different from agreed upon originally |
| seal | mark or impression indicating execution |
| promissory estoppel | principle that bars a party from taking back certain types of promises on which another party relies |
| option | when consideration given in echange to keep offer open for a period of time |
| firm offer | an irrevocable offer |
| illusory promise | appears to be a contract but is not. |
| past consideration | something of value taking place prviously or something that has already been done |
| consideration | exchange of things of value |