1. Contract Defined
A contract is a legally-enforceable agreement between two or more parties.

2. Oral Contracts
Oral contracts are as legally-binding as written ones (save for those that violate the Statute of Frauds).

3. Elements of Legally-Binding Contracts
Offer
Acceptance
Consideration
Legality of the subject matter
Contractual capacity
Contractual intent

4. How to Create a Contract?
Express Contract: one manifested by express words, whether written or oral.
Implied Contract: one manifested by actions.
Quasi-contract: one created by a court in order to achieve fundamental fairness.