Form Follows Function 2

Lesson 3:
Form Follows Function II

In the last lesson, you learned about the distinction between Display Type and Text Type, as well as written or drawn letters and typeable fonts with pre-fabricated letters. Let us look in this lesson at a more detailed distinction between different types of fonts, and the new DIN classification. It is really helpful to learn something about the architecture of letters and their readability.

Albert-Jan Pool, the designer of the FF DIN, developed with the help of Prof. Adler, Ivo Gabrovitsch (FontShop), Ralf Herrmann (Typografie.Info), Otmar Hoefer (Linotype), Peter Karow (former URW), Prof. Indra Kupferschmid, and experts in the field of optics, lighting technology, and visual impairments the new DIN 1450 standard on the readability of typefaces. The norm on readability named previously 35 influences. The new much-improved version, published in 2013, lists 44 influences. 

But the sheer amount of variables that influence readability is less important than the fact that the research group of the old norm did not include type designers. They were able to detect bad readability by testing but unwillingly ignored the typographic reasons for bad readability. Pool designed the diagram below which explains which weight works best for which type of text. 

Source: Albert-Jan Pool

Green: Type for reading texts
This type of font is designed for longer text in books, brochures, instructions, etc. containing the relevant information. They are set in a relatively small size, so big amounts of text use relatively little space but are still easy to read. 

Red: Type for consultation texts
The second type of font is for even smaller sizes. This type supplements or explains the reading text, but does not contain the main information, like for example marginal text, footnotes, or captions.

All: Type for display texts
Fonts for display texts need to draw attention. They structure the reading texts or emphasize parts of them. Examples are the headlines in a magazine or on an advertising poster. As display texts are used in bigger sizes they are designed differently than fonts for reading texts. Often they are more expressive to visualize the tone of the communication. In Visual Identities, they make the Identity recognizable through their expressiveness. 

Blue: Type for signage texts
Fonts for wayfinding or signage systems are the fourth type proposed by DIN. They are used in public spaces for orientation or as indicators of which rules to follow. Although they are used in big sizes, they need to be very easy to read, as they often read when moving in cars or on bikes. 

Not just the line thickness plays a role in readability, but as well the distribution of the weight along the line. Pool writes “The line between good and poor readability does not run between serifs and no serifs or between Antiqua and Grotesk. It is generally the typefaces based on the humanist or dynamic form principle that perform better than those based on the classicist or static form principle.”

To understand this sentence we need to have a look at another diagram by Albert-Jan Pool. 

Source: Albert-Jan Pool

Pool demonstrates here the readability of different types of fonts. He distinguishes between classicist, baroque, and renaissance typefaces, which is basically a distinction between form principles. The classicist distribution of weight in a letter has its origin in the static form principle deriving from writing with a pointed pen, the renaissance type of letter derives from the more dynamic distribution of weight by the broad nibbed pen. The baroque type of letter is a hybrid between these two. 

By blurring the word “handgloves” Pool exemplifies the readability of the typefaces under difficult circumstances, like poor light conditions, driving by the text, being far away from it, etc. It is interesting to see that the type of form principle, classicist, baroque, or renaissance, plays a bigger role than if the font has serifs or it doesn’t. While the rows show the different types of form principles, the columns show the different serifs and no-serif. He starts on the left with a normal serif, the Antiqua, a thicker serif, the accentuated Antiqua, the slab serif, a blocky serif, and finally on the right, a Linear-Antiqua, or sans serif. 

The renaissance or humanist or dynamic form principle is the easiest to read, which is not only due to the more even distribution of weight in comparison with the classicist or modern, or static form principle but also because of the position of the weight, due to the logic of the broad nibbed pen.

Gerrit Noordzij at a special TypeMedia class, 2010. Photo by Tânia Raposo.

Writing with different pens as a base for any type design is an approach that is very much linked to Gerrit Noordzij and his theory of writing. Noordzij (2 April 1931 – 17 March 2022) was a Dutch typographer, typeface designer, and author. He started teaching type design and calligraphy at the Royal Academy of Art (KABK) in The Hague in 1960. His teaching method influenced many generations of now as well famous type designers who now themselves teach the methods of Noordzij. I will tell you more about the theory of Noordzij in the next lesson.


Train your typographic eye and test the readability of fonts yourself. Print a short text in four different sizes, according to the four different types of text mentioned above, and in two humanist and two modern fonts, used by Albert-Jan Pool. Do you see the difference?

Make sure that the width of the column is around, but not wider than 90 characters, and the line height is always optically slightly bigger than the biggest word space. This is especially important for justified text. Long lines with too less line height are hard to read. When using a left-aligned typesetting make sure the right edge is more or less balanced. You always start with a shorter line, the second line is wider, the third line shorter, and so on. You do not want to have distracting shapes on the right edge. Never use right- or center-aligned typesetting for texts.

A small trick for better readability: Big text needs less letter spacing and small text needs more letter spacing. Normal-sized reading texts, around 9-12 pt, should be perfectly spaced by the type designer.

Next Lesson:
Form Follows Tool


DIN Institute Communication:

Berlin, 10.12.2018. The updated DIN 1451 1 “Typefaces – Sans serif linear antiqua – Part 1: General” is intended to support the presentation of information in public spaces such as timetables, lists, notices and signs in easily legible fonts. Up to now, DIN 1451 1 primarily took into account the so-called DIN fonts, which are prescribed in Germany for traffic signs, place-name signs and traffic signs and are also used for most road signs and other signs erected by public authorities. In the new version, DIN 1451 1 provides information on the digital versions of the DIN fonts available on the market today and also recommends some common alternatives. “Since the standard was last updated in 1980, both the technical circumstances and the knowledge about good legibility of type have evolved. Consequently, many new, more legible typefaces have been designed, including sans-serif types,” says Albert-Jan Pool, type designer and chairman of the DIN standards committee responsible for typefaces. “In the revision, our aim was therefore to reflect these developments and help those who plan, design and produce lettering in public spaces to choose the right typeface.”


Translated with

Albert-Jan Pool at Design Made in Germany about the function of serifs and readability:

Who can make a blanket statement about what serifs do for reading? Even in the two most interesting books on the readability of type that have appeared in recent years, “How to Read ” by Gerard Unger and “Reading Letters ” by Sofie Beier, I could not find a clear answer. The circumstances under which we read are too different. At night, for example, we read large brightly lit signposts, during the day the newspaper, somewhat crudely printed or on a reflective iPad, and in the evening a novel by living room lighting, perhaps even candlelight? Reading distance, font size, lighting, font quality vary greatly. All influence the readability of a text.


Translated with

To explore the difference between legibility and readability of reading material, it is important to understand that legibility is a component of readability.

Legibility is an informal measure of how easy it is to distinguish one letter from another in a particular typeface.

Readability is about the reader – the ease with which a reader can successfully decipher, process, and make meaning of the text read.


Albert-Jan Pool was born in 1960 in Amsterdam, Netherlands. He studied at the Royal Academy of Arts in The Hague.

After his study, he moved for Germany. From 1987 to 1991, he was Type Director at Scangraphic in Wedel, Germany. From 1991 to 1994, he was Manager of Type Design and Production at URW Type Foundry. During this time he completed his type families URW Imperial, URW Linear and URW Mauritius.

By January 1995, he started his own studio Dutch Design. FF DIN and FF OCR-F were among his first typeface design projects. He also created the Jet Set Sans, C&A InfoType, DTL HEIN GAS and HEM Headline corporate typefaces. In 2010 he extended his typeface family FF DIN with FF DIN Round and wrote ‘Digital Block Letters’ a small brochure on the history of round sans serif typefaces and the development of FF DIN Round, which was published by FontShop International in 2010.

In 1999, Pool co-founded the design agency FarbTon Konzept + Design. During his time with FarbTon he created the Regenbogen Bold typeface as well as DTL HeinGas Headline. He left FarbTon at the end of 2005.

By January 2006 he started publishing his findings on the history of the German standard typefaces as defined in DIN 1451. Since 2007 he is working on his doctoral thesis on the history of constructed sans serif typefaces in Germany, which is tutorized by prof. Gerard Unger of Leiden University.

He has been teaching type design at the Muthesius Academy of Art starting in 1995, as well as typography at the HAMM Hanseatische Akademie für Marketing und Medien (Hanseatic Academy for Marketing and Media) from 1996 to 1999.

In 2011, the New York Museum of Modern Art (MoMa) decided to extend its collection of applied arts by digital typefaces. Typeface FF DIN was amongst the first set of 23 typefaces which were collected by MoMa.