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First Day Covers are special envelopes that have been postmarked on the first day that a new stamp design has been officially put into circulation by a postal service. These covers often contain uncanceled stamps and may also include additional information or artwork related to the stamp's theme. Collectors of First Day Covers seek out these unique items as a way to document and preserve the history of philately, or the study and collection of stamps and other postal materials. The covers themselves can be made from various materials such as paper, cardboard, or even cloth, and may feature decorative elements like embossing or special cancellation marks. As such, First Day Covers serve not only as a functional means of sending mail, but also as an art form in their own right, appreciated for both their aesthetic and historical value.