A contract is a voluntary arrangement between two or more parties that is enforceable at law as a binding legal agreement.
Elements of contract law
Each contractual party must be a "competent person" having legal capacity. The parties may be natural persons ("individuals") or juristic persons ("corporations"). An agreement is formed when an "offer" is accepted. The parties must have an intention to be legally bound; and to be valid, the agreement must have both proper "form" and a lawful object. In England (and in jurisdictions using English contract principles), the parties must also exchange "consideration" to create a "mutuality of obligation," as in Simpkins v Pays.
A contract is often evidenced in writing or by deed, but a valid contract may (with some exceptions) be made orally or even by conduct. Remedies for breach of contract include "damages" (monetary compensation for loss) and, for serious breaches only, "repudiation" (i.e. cancellation). The equitable remedy of specific performance, enforceable through an injunction, may be available if damages are insufficient.