COLACC (C=Capacity, O=Offer, L=Legality, A=Acceptance, C=Consideration, C=Consent) — six elements of contract formation
ConsiderationEach party must give something of legal value — a promise, act, or forbearance. Past consideration is not valid consideration.
OfferDefinite proposal showing intent to be bound. Must have definite terms: parties, subject matter, price, quantity.
LegalityContract must be for a lawful purpose. Contracts for illegal acts (drug deals, bribery) are void and unenforceable.