Typographical ligature

In writing and typography, a ligature occurs where two or more graphemes or letters are joined as a single glyph. An example is the character æ as used in English, in which the letters a and e are joined. The common ampersand (&) developed from a ligature in which the handwritten Latin letters e and t (spelling et, from the Latin for "and") were combined.

The origin of typographical ligatures comes from the invention of writing with a stylus on fibrous material (like paper) or clay. Businessmen especially who needed a way to speed up the process of written communication found that conjoining letters and abbreviating words for lay use was more convenient for record keeping and transaction than the bulky long forms. The earliest known script, Sumerian cuneiform, includes many cases of character combinations that, over time, gradually evolve from ligatures into separately recognizable characters. Ligatures figure prominently in many historical manuscripts, notably the Brahmic abugidas, or the bind rune of the Migration Period Germanic runic inscriptions.

Medieval scribes who wrote in Latin increased their writing speed by combining characters and by introducing notational abbreviations. Others conjoined letters for aesthetic purposes. For example, in blackletter, letters with right-facing bowls (b, o, and p) and those with left-facing bowls (c, e, o, d, g and q) were written with the facing edges of the bowls superimposed. In many script forms, characters such as h, m, and n had their vertical strokes superimposed. Scribes also used notational abbreviations to avoid having to write a whole character in one stroke. Manuscripts in the fourteenth century employed hundreds of such abbreviations.

Modifications to script bodies like these usually originate from legal, business and monastic sources, with the emphasis shifting from business to monastic sources by around the 9th and 10th centuries.

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