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What’s ephemera. Start with this definition:
the ephemera entry on Wikipedia
EPHEMERA
is transitory written and printed matter, not intended to be retained or preserved. The word derives from the Greek, meaning things lasting no more than a day. Some collectible ephemera are advertising trade cards, airsickness bags, baseball cards, bookmarks, cigarette cards, greeting cards, letters, pamphlets, photographs, postcards, posters, stock certificates, tickets, and zines…
…In library and information science, the term ephemera also describes the class of published single-sheet or single page documents which are meant to be thrown away after one use. This classification excludes simple letters and photographs with no printing on them, which are considered manuscripts or typescripts. Large academic and national libraries and museums may collect, organize, and preserve ephemera as history.