Eivind Bårdsen | Graphic and logo design from the Sunshine Coast

This post is originally an essay I wrote for my typography class at the university. At the end of the post I list some excellent books on typography that I used as my sources.

Introduction

Readability and legibility are two terms used when describing the clarity of a text or a typeface. Although both terms relate to the same subject, they describe two different aspects of clarity. Legibility describes the design of the typeface, while readability describes how the typeface is set on a page. This post will explore the differences between the two terms, and look at how they relate to each other.

Text and display type

Whether type needs to be legible depends on its purpose. Strizver identifies two main categories of type: text and display. Lupton defines ‘text’ as ‘an ongoing sequence of words distinct from shorter headlines and captions’. Jury describes text typefaces as ‘perhaps the most conservative’ group of type. This is because familiarity is a major factor when determining readability, and this is the reason why ‘evolution in the design of text type has … been slow’.

Text type is designed to be legible and readable at small sizes. Display type, however, does not need the extreme legibility and readability needed for long blocks of text. In stead, this kind of type can be more elaborate, expressive and have a more stylish look.

The required level of readability, and especially the legibility, of type depends on whether it is going to be used as text or display.

Display type Rosewood STD

Legibility

Legibility is a term that refers to the design of a typeface. Strizver identifies characteristics such as the size of its counters, x-height, character shapes, stroke contrast, serifs or lack thereof, and weight. Jury defines legibility as ‘the degree to which individual letters can be distinguished from each other’.

Strizver’s characteristics all relate to the ability to tell letters apart. Juryd escribes some of the concerns a type designer has to consider when designing a legible type:

Generally, the most legible typefaces are those with larger, open or closed inner spaces (counters). This inevitably means a generously large x-height. However, if the x-height is ‘over generous’ then, as a consequence, the ascenders and descenders will be too short. This not only adversely affects the legibility of individual characters … but also makes the recognition of word-shapes more difficult.

Capital Cs and Gs in Bodoni and Baskerville look similar.

Jury goes on to argue that ‘problems of legibility are aggravated by intrinsic design features in some typefaces’. Examples are the capital C in Bodoni, Baskerville and Caslon. They have a lower serif that can confuse them with the capital G. Other examples include the cross-barred italic J of Baskerville and Caslon, which looks like the lowercase F, and the italic lowercase H of Garamond can be confused with the lowercase B.

Garamond italic h and b look similar, and so does the Baskerville italic J and f.

Strizver argues that legibility is more of a concern for type used as text ‘where the degree of legibility relates directly to holding the reader’s attention for the duration of the copy’. In order for the reader to bother reading a block of text, it has to be legible. If not, it is too much work.

Strizver notes that display type, in contrast, are ‘generally used for a few words in larger settings where the objective is to be instantly noticeable and convey a mood or a feeling’ . When it comes to display type, legibility is not as important as for text type. While legibility refers to the typeface design, the term readability is about how type is set.

Readability

Readability, in typographic terms, refers to how type is set, or arranged, on a page or a screen. Jury states that ‘good typography encourages the desire to read and reduces the effort required to comprehend. Comprehension is the reason for all reading’. In other words a text should ideally be easy to read and understand. The reader should not need to even notice the type, only understand the words.

As Lupton says it: ‘one of design’s most humane function[s] is, in actuality, to help readers avoid reading.’ Jury agrees and states that ‘all that type requires, finally, is to be readable’.

Strizver identifies some factors affecting readability: ’size, leading, line length, alignment, letterspacing and word spacing’. Other characteristics that help with readability are ‘clean, consistent, uncomplicated design features, more open spacing … and thin strokes that hold up at smaller sizes’. Jury states that readers’ ability to read quickly ‘depends very much on the order and arrangement of type begin “normal”‘ and that ’surprises are disruptive to the mechanics of reading’.

Because people learn to read through their lives, it is easier and faster to digest information in a format they are used to. This is why many text typefaces look ‘conservative’ and uncomplicated.

Both Lupton and Jury argues that there are several scientific studies measuring the readability of a text. Lupton states that a problem with the design industry is that it is ‘ruled, largely, by convention and intuition’. Jury agrees, and notes that designers do not regard scientific research as relevant, when it could help them understand better how type works:

[B]y understanding what factors are involved in the varying degrees of readability, the designer can make adjustments to ensure type functions efficiently where speed of reading and comprehension are of paramount importance.

Readability refers to how well a text is read, and the elements of typography that can improve this. Even though there is a body of research on readability, it seems like designers do not take sufficient advantage of it to improve their work with type.

Conclusion

Two of the most important aspects of type are readability and legibility. Legibility describes a typeface’s design, with all its individual elements. It also refers to how well individual letters in a typeface can be distinguished. Readability has to do with how the text is arranged. It deals with the size of the text, the space around it and so on. Scientists have done research on readability, but several typographers are upset that designers do not draw enough on this research when they design or set type.

List of references

Jury D, 2004, About Face: reviving the rules of typography, RotoVision, Switzerland.

Lupton E, 2003, ‘Science of Typography’, Print Magazine, Summer 2003, viewed 30 June 2008.

Lupton E, 2004, Thinking with type: a critical guide for designers, writers, editors, & students, Princeton Architectural Press, New York.

Strizver I, 2006, Type rules! : The designer’s guide to professional typography, John Wiley & Sons, New Jersey.

What do you think? Do you agree with Jury, Lupton and Strizver, or do you have other definitions?