What is Contract Law?
Contract law is the body of rules that determines when a promise or agreement becomes legally binding and enforceable. It sets out what a valid contract needs, when it can be broken, and what remedies are available if it is.
A contract is a legally enforceable agreement formed when there is an offer, acceptance, consideration, capacity, and a lawful purpose between the parties.
- 1↓OfferOne party proposes specific terms to another, showing willingness to be bound if accepted.
- 2↓AcceptanceThe other party agrees to the exact terms of the offer, creating mutual agreement ('meeting of the minds').
- 3↓ConsiderationEach side gives something of value — money, goods, services, or a promise; a one-sided gift is not a contract.
- 4↓CapacityBoth parties must be legally able to contract — of age, of sound mind, and not under duress.
- 5↓LegalityThe purpose and terms must be lawful; agreements to do something illegal are unenforceable.
- 6Binding ContractOnce all elements are met, the agreement becomes enforceable in court.
Step-by-step worked examples
A store sells a jacket for $50 and a customer pays at checkout. Is this a valid contract?
Offer: the store displays the jacket at $50, inviting purchase. Acceptance: the customer accepts by paying, and the store accepts by handing over the jacket. Consideration: $50 for the jacket — value flows both ways. Capacity and legality are satisfied → yes, a valid, binding contract is formed.
A friend promises to give you their old bike for free, with nothing expected in return. Is this an enforceable contract?
There is an offer (the promise) and possibly acceptance. But there is no consideration — nothing of value flows back from you to your friend. Without consideration, this is a gratuitous promise, not a legally binding contract.
A 15-year-old signs a contract to buy a car. Is it enforceable against the minor?
Offer, acceptance and consideration may all technically be present. But capacity is missing — minors generally lack full contractual capacity. Such contracts are typically voidable at the minor's option, not automatically binding on them.
Flashcards
Quick quiz
Q1.Which of these is NOT one of the essential elements of a contract?
Q2.A promise with nothing given in return is generally…
Q3.Contract 'capacity' refers to…
Q4.If a contract's purpose is illegal, the contract is…
The full card deck, worked steps and AI-tutor support for “What is Contract Law?” are in Notek — study by hand before your exam.
Common mistakes
A contract must always be in writing to be valid. — Correct: Most contracts can be oral; only certain types, like land sales, legally require a written form.
A gift is the same as a contract. — Correct: A gift lacks consideration from the recipient, so on its own it isn't a legally enforceable contract.
Anyone can sign a fully binding contract. — Correct: Parties need legal capacity — minors and people lacking mental capacity have limited or no contractual power.
Agreeing to different terms than the original offer counts as acceptance. — Correct: Acceptance must mirror the offer's exact terms (the 'mirror image rule'); changed terms are treated as a counter-offer, not acceptance.
FAQ
What is contract law?
Contract law is the set of rules that determines when an agreement between parties becomes legally binding and how it can be enforced or remedied.
What are the elements of a valid contract under contract law?
A valid contract needs an offer, acceptance, consideration, capacity of the parties, and a lawful purpose.
What are examples of contract law in daily life?
Buying groceries, signing a phone plan, renting an apartment, and taking a job offer are everyday examples governed by contract law.
How to determine if a contract is valid?
Check that there is an offer, a matching acceptance, consideration exchanged, legal capacity of both parties, and a lawful purpose — if any element is missing, the contract may be unenforceable.