Tegnformer

Tegnformer are the visual shapes used to represent signs in a writing system. The term describes the graphical realization of a sign—the glyph—distinct from the abstract sign or grapheme. Tegnformer can vary across fonts, sizes, handwriting styles, and historical periods, and they include ligatures, letters with diacritics, and contextual variants produced by different scripts.

In practice, tegnformer cover several phenomena. Latin scripts exhibit ligatures like fi or fl, and can feature stylistic variants such as uppercase and lowercase forms or historic forms such as the long s. Arabic script uses contextual tegnformer that change shape depending on whether a sign is isolated, initial, medial, or final in a word. Devanagari and other abugida systems display conjunct forms when multiple signs combine. In Chinese and other logographic systems, tegnformer are typically stable across fonts but can vary in stroke weight or calligraphic style.

In the digital domain, tegnformer correspond to presentation forms of characters in fonts. Unicode provides abstract code points for signs; fonts map these to concrete tegnformer. Some writing systems also use presentation-form blocks or stylistic sets to switch between alternative tegnformer without changing the underlying text. Understanding tegnformer is important in paleography, digital typography, OCR, and font design, where the relationship between abstract characters and their graphical realization affects readability and interpretation.