What is bar border?
bar border meaning in Information Science terminology / glossary / dictionary is:
A decorative band running the length of one of the margins of a page in a medieval manuscript, usually along the left-hand side of the text but sometimes along the right-hand side on the recto. Click here to see a floral example in a 15th-century Dutch Book of Hours (Cary Collection, Rochester Institute) and here to see a strewn example in the 15th-century Hours of Dionora of Urbino (British Library, Yates Thompson 7). A bar border may begin as an extension of a large initial letter (see the Fleur des histoires de la terre d’Orient, courtesy of the Bibliothèque Nationale de France) and is often embellished, sometimes in gilt, as in the Burnet Psalter (University of Aberdeen Library, AUL MS 25). Bar borders are sometimes used to separate columns of text, as in the 14th-century Image du Mond of Gossouin de Metz (Bibliothèque Nationale de France). Some bar borders support playful bas-de-page scenes. See this example, courtesy of the British Library (Burney 275).