In its general sense, an offer is an indication or proposal by one person or party (offeror) to another (offeree). It consists of one party promising to do or give something for the other party’s promise to do or give something in return. There must be willingness to contract on certain terms, made with the intention that it shall become binding as soon as it is accepted by the person to whom it is addressed.
An offer can be given in one of many forms which are: letter, newspaper, fax, email, and conduct (if suitable and all terms are understood by both parties). There are also different types of offers, one which involves a specific individual or group, and one which refers to the world as a whole. A unilateral offer is an offer which the offeree accepts by performing his or her side of the bargain. A bilateral offer is responded to with an exchange of promises between two parties.
Another area in making an offer is an invitation to treat. This is not an offer, but an indication of a person’s willingness to negotiate a contract. Or in other words, it invites someone else to make an offer for what they are displaying. An example of a case where an invitation to treat was present was in Fisher V Bell, it was established that, where goods are displayed in a shop together with a price label, such display is treated as an invitation to treat by the seller, and not an offer. The offer is instead made when the customer presents the item to the cashier together with payment. Acceptance occurs at the point the cashier takes payment.
One of the rules of an offer concerns its termination. An offer may come to an end in various ways. So long as this happens before acceptance then there cannot be a contract. (Of course if someone tried to withdraw an offer after acceptance, this would simply be a