Offer, acceptance, consideration

Offer or proposal- 

Promisor 

Promise

 Reciprocal promises

Promisee 

General offers and invitation to offer 

Acceptance 

 Revocation of acceptance 

Agreement - offer or proposal accepted becomes a agreement 

Contract - agreement enforced by law becomes a contract 

Valid contract 

1. Made by person competent 

2. By free consent (not by coercion, undue influence, fraud, misrepresentation, mistake) otherwise voidable 

3. lawful 

Implied - conduct 

and express - writing or oral 

 Standard contract 

1. Employment contract 

2. Receipts

Consideration

Promissory estoppel 

 Acts done at request

 Acts for charitable purpose

Privity of contract