An exhibition, in the most general sense, is an organized presentation and display of a selection of items. In practice, exhibitions usually occur within museums, galleries and exhibition halls, and World’s Fairs. Exhibitions can include many things such as art in both major museums and smaller galleries, interpretive exhibitions, natural history museums and history museums, and also varieties such as more commercially focused exhibitions and trade fairs. The word “exhibition” is usually, but not always, the word used for a collection of items. Sometimes “exhibit” is synonymous with “exhibition”, but “exhibit” generally refers to a single item being exhibited within an exhibition. Exhibitions may be permanent displays or temporary, but in common usage, “exhibitions” are considered temporary and usually scheduled to open and close on specific dates. While many exhibitions are shown in just one venue, some exhibitions are shown in multiple locations and are called travelling exhibitions, and some are online exhibitions. Though exhibitions are common events, the concept of an exhibition is quite wide and encompasses many variables. Exhibitions range from an extraordinarily large event such as a World’s Fair exposition to small one-artist solo shows or a display of just one item. Curators are sometimes involved as the people who select the items in an exhibition. Writers and editors are sometimes needed to write text, labels and accompanying printed material such as catalogs and books. Architects, exhibition designers, graphic designers and other designers may be needed to shape the exhibition space and give form to the editorial content. Organizing and holding exhibitions also requires effective event planning, management, and logistics.