A postcard or post card is a piece of thick paper or thin cardboard, typically rectangular, intended for writing and mailing without an envelope. Non-rectangular shapes may also be used but are rare.
In some places, one can send a postcard for a lower fee than a letter. Stamp collectors distinguish between postcards (which require a postage stamp) and postal cards (which have the postage pre-printed on them). While a postcard is usually printed and sold by a private company, individual or organization, a postal card is issued by the relevant postal authority (often with pre-printed postage).[1]
Production of postcards blossomed in the late 19th and early 20th centuries.[2] As an easy and quick way for individuals to communicate, they became extremely popular.[2] The study and collecting of postcards is termed deltiology (from Greek deltion, small writing tablet, and the also Greek -logy, the study of).[1]
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