1. Whether or not it has serifs.
2. The shape of the serifs, if any.
3. The difference in the change from thick to thin in the strokes of the letters.
4. The direction of the thick part of a curved letter from – known as the “stress’.
5. The average width of the characters – called the “set”.
– Modern, or Didone
– Slab serif
– Sans serif
– Decorative and Display
– Script and Brush
These divisions are very broad. Many typefaces, particularly of recent design, have characteristics which belong in more than one group.
Old face types usually have lightly bracketed serifs, with a moderate change from thick to thin strokes in the letter and an oblique stress in the direction of the thick strokes. The italic form is usually slightly decorative. The letters tend to be light in weight, although the type family usually includes a bold version.
Transitional types have serifs that are more clearly bracketed and have a more marked, but not abrupt, change from thick to thin strokes. There is a less obviously oblique direction in the heavy part of the letter.
Modern types have fine, unbracketed (hairline) serifs with a strong contrast between thick and thin strokes. There is a strong vertical stress in the direction of the heavy parts of the letters.
Slab serifs have, as their name implies, noticeably heavy, rectangular serifs. The design of the rest of the letter can vary but there is usually little difference between the thick and thin parts of the letters.
Sans serifs are all types without the termines strokes (serifs) at the ends of the stem, arms and tails of the letters.
Decorative and Display are intended to be used for only a few words at a time. They are not suitable for continuous text.
Script and Brush letters have an informality which is useful in publicity and display work but makes them unsuited for long text passages.
Old English, or Blackletter types, are based on the formal, mediaeval, pen forms. They have a distinctive period flavour but are usually difficult to read for more than a few words.
Although there is no scientific evidence to prove it, many people feel that serifed types are more comfortable to read over a long, continuous text.
Sans serifs look clean and business-like. They normally have a very wide range of weights, which makes them particuarly useful in publicity and display. Sans serifs reproduce well on a smooth, matt paper that does not reflect the light.
Light weight alphabets with fairly short serifs and little difference between thick and thin strokes tend to look their best at h igh resolution, printed on a matt or rough paper.
Types with more robust serifs and a clearer difference between thick and thin strokes stand up better to low resolution and reproduce well on a wider range of papers.
Types with very fine serifs and a strong vertical stress look better if produced at higher resolutions. The sharp contrast between thick and thin strokes is best maintained on a smooth paper surface.
If the column width is narrow, then avoid typefaces with a very wide set. But remember that types with a very narrow set (condensed) can be tiring to read over a long text.
Many typefaces are available in families of weights and other variations from condensed to extended. The advantage of working within one family is that you can be sure that the types will combine well and the contrast between one weight and another will be sufficient for the reader to notice the difference. It is rarely necessary to use more than two or three weights in one document but in any case be sure to use them consistently.