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Without serifs: a sans by any other name »

Recently, a question by Cynthia Batty on the ATypI mailing list led me to do a quick survey on what we call typefaces without serifs. Click here to take survey.

Here are the results of my little survey. There have been over 300 responses. It’s certainly not a random sample, mostly people deeply involved with typography in some way. Interestingly, the results didn’t really vary by expertise level. (The order of the possible answers was randomly varied so as not to influence the answers, btw.)

The most common comments under “other” were that it should be “sans serif” as a noun and “sans-​serif” as an adjective (for example, “a sans-​serif typeface”). Certainly if the noun form is “sans serif” then standard English usage would dictate that the compound adjective would be hyphenated.

Another common response was that “sans” is an acceptable informal shorthand for “sans serif.”

Finally, it seems that despite a bit of solid support in the UK for “sanserif,” that spelling is neither particularly widely used nor accepted. The Oxford English Dictionary accepts it and dates it back to 1830, and the Oxford University Press, Robert Bringhurst (The Elements of Typographic Style) and eminent professors James Mosley and Michael Twyman all use it, as does typographer and typography author Robin Kinross. I must confess to not much liking “sanserif” myself.

[Edited to correct spelling of “Mosley” and add a little more detail on “sanserif,” and again to add Bringhurst the to list of “sanserif” supporters.]

Point Size and the Em Square: Not What People Think »

It’s easy enough to determine that a point is 1/​72 of an inch, and used to be about 1/72.27 in the days before digital type. But the challenging question is, when you look at printed type on a page, what part of a 12-​point font is 12 points high? The short answer is “none.” Seriously. For metal type it’s the “body” which is not something you see in print, and for digital type it’s the “em,” which is completely virtual.

Font Size Measurement Confusion

The background to this is long and complicated, so I hope you’ll forgive me if I first explain how this is the question that just refuses to die, and the confusion it can cause… in painful detail.

Historical Background

Back in the days of metal type, the answer was simple, even if it didn’t relate to anything one saw in the printed output. The point size of the type was simply the height of the metal body the type was cast on. Additional line spacing was added by means of thin strips of lead between the lines, hence the term “leading” (pronounced “ledding”) for line spacing.

Metal type, showing point size

Above is shown a piece of traditional metal type (photo courtesy Daniel Ullrich, licensed under Creative Commons Attribution Share-​Alike 3.0). The added red bracket shows the body height, which one would measure to determine the type size.

In metal type, without leading, the distance from the baseline of one line to the next would be the same as the point size. However as you can see in the example, once the metal type was printed, there was no direct means of knowing what the original point size had been, unless one also knows either the original typeface or the amount of leading used with some certainty.

Today’s Answer & Implications

In digital type, the font’s letters are drawn on a grid, where an arbitrary number of units (often 1000 or 2048) are set to equal the “em” which is then scaled to the current point size for output. So to get 12 point type in print, with a 2048-​unit em, that digital space is scaled so that the 2048 units in the design space are equal to 12 points. As Karsten Luëcke put it in a recent discussion on Typophile:

In digital type, the EM does not refer to a “real” box. You better consider the EM as a yardstick – an abstract letter-​height yardstick which establishes a link between micro and macro level, between font-​internal unit system and font-​external unit system: The font-​internal unit system is defined via UPM, i.e. as the number of units per EM. It is the letter-​design grid or resolution. The font-​external unit system may be typographic point, millimeter, pixel, etc. And this abstract EM serves to project the font-​internal unit system onto the font-​external unit system.

An example. You have a font with 2048 units per EM, internally, which is to be projected on 12 pt type size, externally. So 12 pts = 2048 M-​units or 1 M-​unit = 12/​2048 pt.

So to image the font at 12 point, one scales the abstract EM to equal 12 points.

The catch for purposes of measurement and standardization is that while there are some restrictions on how large one can draw letters in the design space, there is no necessary and required relationship between the size of the letters and the em. On average, with Latin-​based languages such as English, the “cap height” of capital letters is about 70% of the point size, and the “x-​height” of lower-​case letters is about 70% of the cap height, or about half the point size. But (and I cannot stress this enough), those are only averages, and there is no technical requirement whatsoever that one be close to those averages. Indeed, x-​height relative to cap height is one of the ways typographers describe typefaces (“high x-​height” vs “low x-height”).

[UPDATE : I did some research for a client, and verified that as expected, cap size varies substantially between different fonts. In my sample, cap size was most usually 62%-78% of the em square, averaging right around 67-​70%. Or to put it another way, if you take an “average” font printed at a given point size, other fonts at the same point size will commonly have capitals as much as 10% smaller or 10% larger than the capitals from the average font. At the extreme you can find fonts “in the wild” with caps barely over half the average size! (I expect you could also find fonts with caps close to half again the average size, but I wasn’t looking so hard in that direction.)]

Moreover, the Zapfino example given earlier shows how a given font could be at a radically different size relative to the point size and still be a legitimate font. Indeed, anyone knowledgeable in modifying fonts could in a matter of minutes, take almost any font and create a modified version, with the only visible difference being that text at a given point size is only a fraction of the size.

What About the Web?

The web can use points, but just defines them in terms of pixels. It has inherited the Windows definition of that ratio, so on the web by default 1 pt = 4/​3 pixels, so 12 pt = 16 pixels (but see below).

It used to be that Mac browsers used the Mac relationship of points to pixels, which was one-​to-​one, but that has been abandoned just a few years ago. so at least points vs screen pixels are now consistent across platforms, though how big a point is on screen (or a nominal browser pixel for that matter) depends on your screen resolution, what zoom level your browser happens to be set to at the moment, and (on Windows) whether you have set something other than the default screen resolution of 96dpi.

But the relationship between pixels and points is broken in some browsers on Windows (such as Internet Explorer 7 and earlier) when the user has a non-​standard resolution set. For example, if you actively tell Windows your screen resolution is 120 dpi instead of 96 dpi, that means that point sizes get multiplied by 5/​4, but sizes in pixels do not. So at 120 dpi, a font set to 9 pt will instead show up at 15 px, but a font set to 12 px will still be 12 px, and now smaller. Arguably this is a reason never to do font sizes in px. (Bitmapped grapics generally are not scaled by the 5/​4 ratio in browsers, but they are in other apps such as Word or the usual graphics previewing programs.)

This may get even less standard in the future, as CSS 3 is threatening to make pixels a truly imaginary thing, always equal to 4/​3 the point size. This would cause pixels to scale into virtual pixels when non-​standard resolutions are set.

Of course, some users (like me) are constantly changing the zoom level in their browsers, which also plays hob with any notion of fixed sizes for points, though at least relative sizes are maintained by browser zoom.

Things get kinda weird on the web, in another regard. CSS can use “ems” as a measurement unit. Okay, that makes sense, right? I mean, why not set an indent or margin in ems? No problem. Where it gets weird is that you can set the type size in ems. Now, logically based on the “normal” definition of the em, this makes no sense, because the size of an em is always the same as the type size, so the size of the type is always one em. But CSS allows you to break that assumption by setting an em to some specific number of points or pixels, and then setting the type size to some multiple of that. It gets even weirder, actually, because you don’t need to define the em in the first place. If you don’t define it, the standard browser assumption is that one em = 16 pixels (Firefox and possibly Chrome), or 12 points (Internet Explorer). The difference between IE and the rest doesn’t matter with default Windows resolutions, but it gets interesting at non-​standard Windows resolutions because IE then scales the default em, while Firefox does not…. Ouch.

[Note: edited and expanded this section several times on 21 March 2011 to better reflect system scaling setting issues. Thanks to Beat Stamm for pointing out the omission and helping me with details I hadn’t yet encountered.]

How to Legislate Type Size Today?

First, a disclaimer: One can implement reasonable precautions, but it’s not possible to stop determined people with sufficient knowledge of fonts and typography from creating customized fonts, which can in turn be used to create either illegible documents, or disclaimers that most people would never read. To even attempt to cover all possibiities would probably yield many pages of added law, which frankly somebody like me could probably still find a loophole in with a moderate investment of time and thought. What reasonably can be done, however, is to make the laws tight enough that it would take significantly more expertise, creativity and effort to work around them than is currently the case.

So what variables does the law need to control when it wants to legislate a minimum size and legibility?

Most common system fonts a reasonable person would think of using would mee these requirements, including Times/​Times New Roman, Arial, Helvetica, Courier/​Courier New, Verdana, Trebuchet, Georgia, Calibri, Consolas, Constantia, and Corbel.

Of course, I’ve only addressed the font size part of the equation. There are many other components to legibility of text in print, such as line spacing, letter and word spacing, line length, and the color of the text and the paper.

[EDITED various times to clarify minor points and improve wording. Most recently to correct that Zapfino was rescaled by 2.5x, not 4x, and replace a dead link.]

ADDENDUM 16 August 2012:

This stuff just doesn’t go away! A recent decision of the Michigan Supreme Court hinged on exactly this issue. The underlying subject matter was the hottest state political issue of recent years, an attempt to put in place a ballot measure that would in effect stop the ongoing removals of collective bargaining rights for folks doing business with cities. Here’s the Detroit Free Press about the case, and the actual court decision (including concurring and dissenting opinions).

It’s not a “screen font” any more »

Funny, the other day I had just finished a first pass at reviewing and revising the Extensis document on “Best Practices for Font Management in Mac OS X,” when a non-​Extensis colleague asked me something about PostScript Type 1 fonts: whether Windows .pfm and .pfb files were pretty much equivalent to Mac screen and printer font files.

What was funny to me was that only half an hour earlier, I had just been adjusting the language about “screen fonts” and “printer fonts” in the Extensis doc.

Anyway, here’s what I said:

First, on *both* Mac and Windows, the phrases “printer font” and “screen font” make no sense any more when referring to the pieces of a Type 1 font. The last time those phrases made sense was at the beginning of the 1990s, before everyone started using ATM, which scaled the outline font (then called a “printer font”) for display on screen. This function has been long since taken over by the Mac and Windows operating systems around 1999-2000.

Heck, Mac OS X isn’t even capable of using the bitmaps from the font suitcase for screen display at all, so it really isn’t a screen font any more.

So, the “screen font” isn’t used on screen, and the “printer font” is used both on screen and on printers.

Which is why I prefer to use the terms “font suitcase” and “outline font.”

The font suitcase for a Type 1 font contains kerning information, which is useful, and bitmaps, which are required, but not actually used anywhere any more… it’s just that you need at least one bitmap size per font. BTW, one font suitcase can contain bitmaps for multiple outline fonts.

The outline font is what it sounds like, the actual scalable outlines of all the glyphs in the font, as well as some platform-​independent info such as the PostScript FontName, FullName, yadda yadda.

Oddly, both the suitcase and the outline font contain advance widths—the amount of space allotted for each glyph, including white space on either side of it.

Finally, to answer my colleague’s question? Yes, the Windows .pfm and .pfb files are pretty much equivalent to the Mac font suitcase and the outline font (exactly equivalent in the case of the outline font and the .pfb). The .pfm file doesn’t have bitmaps, but it has other platform-​specific info, like the font suitcase.

Of course, font suitcases can also be containers for Mac TrueType fonts, but that’s another story….

[updated 27 Apr 2009 to clarify OS X not using bitmaps at all]

Font terms survey results »

I had 315 respondents before I closed off my survey on font terms. In general, the results were along the same lines I would have quessed, but less strong/​clear in many areas, and there were a couple of surprises.

(On a side note, I am currently recovering from jaw surgery this past Monday. The surgeon cut through my jaw in three places, and also removed three wisdom teeth. So I’m a wee bit sore….)

SUMMARY

There is no consensus, but the overall opinion is that in today’s world of digital typography “a typeface” means the general design, including all its styles, regardless of how it’s instantiated, while “a font” means a single style of a typeface, such as Myriad bold condensed italic, in a specific file format.

This is the same usage I prefer, but I’ll point out that there are some smart people who are prominent typographers who disagree. However, they’re in the minority, even among type industry professionals (which I will sometimes refer to as just “industry” in the results).

There doesn’t seem to be any single preferred terminology for indicating a “superfamily,” which might contain related typefaces, such as Stone Serif and Stone Sans.

The most popular term for a family of only up to four linked font styles, including bold and italic, seems to be simply “family,” to my surprise.

The painful details below are probably only of interest to hard-​core font geeks, and while writing it up I wondered if I was perhaps getting a little too detailed….

ANALYSIS

I used features of SurveyMonkey to do such things as randomize the order in which different answer options were shown from one user to the next, to avoid any systematic bias due to presentation order.

I analyzed the differences between groups looking at both font expertise and geography (questions 8 and 9). Geography rarely made a significant difference in results, but level of font expertise often did.

(Sorry this analysis has taken so long, I’ve been remarkably busy with other things lately, such as being diagnosed with diabetes and getting a new job. I expect to remain pretty busy for the next couple of months, so my blog posts may be few for a while.)

SEE FOR YOURSELF

You can see the survey results yourself, as aggregate results in simple charts on SurveyMonkey.

You can also look at these PDFs I made of the results. Sorry about the lousy page breaks in them, but they retain the formatting of the SurveyMonkey HTML version, and show the various filters I applied:

In general, I didn’t find much interesting difference by geography, and the differences by expertise seemed to be on a fairly linear scale. That is to say, the more “advanced users” were always in between the industry professionals and the regular graphic designers in their take on any given issue. I was most interested in the opinion of industry pros, but if this differed a lot from more common usage, that was interesting, too.

ANALYSIS

I report below on each question, and commenting when some particular sub-group(s) answered that question significantly differently than the average. I analyzed results by level of font expertise, and by geography.

Question 1

Q1. What are the differences between a “font” and a “typeface”? (You can check ALL that apply)

With increasing expertise, people were much more likely to pick the “abstract design” option and somewhat less likely to go for “more than one style.” Type industry professionals went 73%/48% on these, while average users went 46%/63%, differences of 27% and 15%, respectively.

Given the industry expert responses on question 2, I think one key issue here was that a typeface can have more than one style, but doesn’t necessarily. The other key thing is that there is much more consensus around the definition of “font” than the definition of “typeface.”

Question 2

Q2. When talking about scalable digital fonts, what constitutes “a font” in your mind?

Question 3

Q3. Which of the following elements is part of the definition of “a single typeface” in your mind? Check ALL that apply.

Question 4

Q4. How appropriate would you say each of the following terms is for meaning a single face/​style of a font family in a given format, such as Helvetica Bold Condensed Italic in OpenType CFF?

Available responses ranged from “Absolutely Not” (1) to “Fits Perfectly” (6). So for each term, one can give the average rating on this 1-​6 scale, as well as percentages who gave each specific rating.

Question 5

Q5. How appropriate would you say each of the following terms is for use in describing a style-​linked group of up to four fonts (regular, italic, bold, bold italic)?

Same response options as above, yielding the same 6-​point scale equivalent.

Question 6

Q6. How appropriate is each of the following terms for describing a typeface family with an arbitrary number of styles? For example, they could vary in weight, width, slope, optical size, and possibly other minor stylistic ways.

Same response options as above, yielding the same 6-​point scale equivalent.

Question 7

Q7. What’s the best term for describing a set of related fonts/​typefaces/​etcetera that differ in major design characteristics? For example, there might be a serif, a sans serif, a monospaced semi-​sans, and a slab serif version, each in turn comprising a full type family (or whatever one calls them) of its own. You construct a term by combining an adjective (options across the top) with a noun (options down the left side). This creates combined terms such as “type series” and “font suite.” Please check ONLY ONE BOX for this question, unless you feel there are two or more equally good first choices.

i sort of threw this question in to attempt to explore the question, and maybe narrow the range of reasonable options a bit.

Collection,” “Extended Family,” and “Suite” were the most popular main terms, with optionally sticking in “Typeface” as in “Typeface Collection,” “Extended Typeface Family” and “Typeface Suite.”

Personally I prefer “Type” as an adjective if one is to be used at all, but that was only popular in conjunction with second-​tier popularity terms such as “Type System” and “Type Series.” (The other second-​tier term was “Super-​family” which was most popular with no qualifier at all, or with “Typeface.”)

I don’t really get why anybody would want to put “Typeface” and “Family” in the same term. It seems redundant to me.

Other terms ranked much lower, including “Type Series,” “Typeface Meta-​family,” “Clan” and “Uber-​family.”

Question 8

Q8. How deeply involved are you with fonts and typography?

Q9. Where are you from, and where do you live?

(Update: I deleted the chart version of this, because SurveyMonkey really made a mess of what it did with percentages. But the results are….)

Mostly educated in:

(Adds up to more than 100% because some people checked more one location, and because of rounding.)

Live:

Almost identical to the results for “educated.”

[Post updated 8 April 2009 to correct a couple of minor transcription errors. These did not materially effect the results, being differences of 0.5% and 1.5%. – T]
[Post formatting updated 3 May 2011 to work better with current CSS template.]

A font by any other name? »

[UPDATE 5 Mar 2009: Survey is now closed. I am analyzing and writing up the results.]

I’ve noticed over the years that there isn’t a perfect consensus on the use of certain terms, such as “font” and “typeface.” I am of the opinion that there is a strong majority usage, and historical precedent, but I’m curious to understand better current usage, and how it differs by degree of font expertise (a.k.a “geekiness”) and/​or geographic location.

Please take my survey. I’ll let it run until I feel like I’ve got enough responses, then I’ll post the results and my analysis.

I’m eager to learn more. Is there a gap between expert usage and the average user? Maybe we’ll discover that I’m just a stick in the mud regarding terms that have mutated over time… or maybe I’ll get ammunition to defend the Wikipedia definitions from the clueless, and persuade type foundries to standardize their langauge. Stay tuned!

SPOILER ALERT! Please don’t read the comments below until after you’ve done the survey! There are definitely some… well, not spoilers, but potential influencers and links to other pieces on the subject. Thanks!

[UPDATE: Survey results are here.]