In addition to housing medieval manuscripts and incunables, the Library of Congress also holds a significant collection of facsimiles of these items. They include facsimiles of medieval encyclopediae, poems, bibles, maps, etc. Some of these facsimiles may be requested in the Main Reading Room or in the Rare Book Reading Room. Manuscripts and incunables must be requested in the Rare Book and Special Collections Reading Room. This guide provides an overview on how to search for these materials in the Library and provides some supplementary information on scribal abbreviations and a glossary of technical terms.