Schlagwort-Archive: Antiqua

Ligatures and contextual alternates

The self‌less butterfly. Or: Using and avoiding ligatures.

Typeset letters of the Latin alphabet are typically unconnected – such as the ones you are reading right now. There are typefaces in which letter shapes (glyphs) appear mostly connected (e.g., styles mimicking handwriting or calligraphy). In this piece, though, I will focus on typefaces in which most glyphs are not connected to their neighbours, but separated from them by a certain amount of white space.

Even in such typefaces, there are cases in which letters are represented by a connected shape. This is referred to as a ligature. There are two common reasons for using ligatures: First, the juxtaposition of letters in a word can lead to an overlap of shapes that is considered aesthetically displeasing by the designer. Adding more white space between the shapes does not always resolve the problem in a way that is seen as satisfactory. Sometimes it is perceived as a better solution to merge the overlapping shapes into one shape that represents several letters. Second, ligatures can also be used for decorative purposes, when shared shapes are created for letters that normally would not overlap.

In digital typesetting, a ligature that deals with an unwanted overlap is referred to as a ‘standard’ ligature (OpenType feature liga) – shown in the top part of the picture below. The overlapping glyphs are highlighted in red; the ligature glyph in which the accidental overlap is replaced by a smooth connection is highlighted in blue. A decorative ligature is a ‘discretionary’ ligature (OpenType feature dlig) – shown in the bottom part of the picture. The glyphs highlighted in green do not overlap; when a connecting element is added, this leads to the blue ligature glyphs. Discretionary ligatures are often used sparingly and, as the name indicates, at the typesetter’s discretion. Their use will not be discussed here. (The serif typeface used for all the samples in this article is Noort by Juan Bruce.)

Standard ligatures and discretionary ligatures

In this piece, I would like to argue the following:

  • It is preferable to avoid standard ligatures (i.e., ligatures used for dealing with glyph overlaps) and to handle overlaps in a way that keeps letter shapes unconnected.
  • If standard ligatures are used, their use must be in line with language-specific structural rules. Unconnected alternatives must be provided for all ligature pairs.
Identical zero and oh glyphs

Zero vs. oh: Strategies of glyph differentiation

When characters look similar to one another, misreadings or even misunderstandings may result. In such cases, type designers often try to avoid glyphs looking completely identical. One example of a similarity that can get too close for comfort is between the digit ‘0’ (henceforth: zero) and the letter ‘O’ (oh). Differentiation strategies between lining zero and upper-case oh have been shown to be fairly uniform across typefaces: Zero is almost always narrower and often less tall than Oh. These and other strategies have been discussed in a 2013 article by Charles Bigelow. He focuses on lining figures in typewriter typefaces and only briefly mentions contemporary approaches to non-lining zero and lower-case oh – a pair that is also prone to confusion and seems to be treated with less uniformity in recent typefaces. Inspired by a tweet by Shiva Nallaperumal, I have compiled typical and not so typical ways of distinguishing non-lining zero from lower-case oh. My observations are mainly based on old-style roman text typefaces in the Typekit library; this sample is not representative of anything but the Typekit library itself, which, however, contains a bunch of well-known, widely used typefaces.