Wednesday, August 18, 2010

Without Flair - Safe computer use means Safe fonts

The title of this post might be a little inflammatory to folks who get really uppity about 'nice' fonts.
( If that means *you* then this article is maybe not going to be to your liking. )

Fonts that are screen friendly Sans-Serifs, such as DejaVu Sans Mono* or Liberation Mono, might better be described in a sentence as:
Having fewer finishing touches and spaced as if letters were punched individually, rather than closely packed handwriting placement.

Here is a typical Sans-Serif:

...and for comparison here (below) is a Serif:

take a look at the right hand floor kicker on the letters a and u in the second example. These are sometimes referred to as "finishing touches". If you were handwriting non-joined letters, then you would touch these extra bits of ink perhaps after the main bulk of the character was done...hence a "finishing touch"

Now look instead at the a and u in the first example and see that they do not have those finishing touches.

Now look at the first five characters in each example and note the difference in the spacing.

Comprehension of text on computer screens:

The examples above are probably too short to really make a noticeable difference in how you comprehend what is written.

A paragraph of text with one or more full sentences is needed, but it also depends on the particular Sans-Serif and Serif that you choose.

Decide which of these three Sans-Serif sentences you prefer:




now decide which of the three you like...

...and I will label them below...

Note: Pay attention to the style, rather than how clear the image is on your screen. Using an image means you might have to click the image to get a clearer representation, however you see the exact font with no substitution by your browser.

  1. DejaVu Sans Mono
  2. Liberation Mono
  3. FreeSans

Which did you prefer?

Note: I did not disfavour FreeSans by making it smaller for any particular reason, it was just that blogger resizing seemed to blur
it more than the other two when using the largest resize option.

On my computer the examples were all produced at 12 point in OpenOffice, exported to PDF and then Okular selected saved to .jpeg files.

I expect the results to be okay but not fantastic and I think that is what I have got.
The original .pdf and OpenDocument text files are available at this directory for you to download and open locally (repeated below).

  • .pdf file with paragraphs for comparison of the Sans-Serif fonts
  • .odt file* with paragraphs for comparison of the Sans-Serif fonts

*You will need LibreOffice or OpenOffice to open OpenDocument Text files (.odt) , and those Office suites can be downloaded from and respectively.

If you have not had much experience with using Pdf files across different platforms, then you might be interested to see what/how the fonts are embedded into the .pdf that I have generated.

If, when you open them on your computer, the .pdf and .odt look different somehow, then it maybe that your computer is doing some font replacement. The .pdf has the fonts embedded so there should be no font replacement there I hope!
If your OpenOffice is doing some font replacement then consult Tools -> Options within OpenOffice:

The Fonts screen shown above will have a tick in the box for "Apply replacement table" and you should see the replacements listed in the box in the middle of that dialogue.

Safe fonts - what is that supposed to mean in the title?

There is some speculation, that having fonts that are well spaced and designed for viewing on electronic displays, might help users with symptoms of Computer Vision Syndrome (CVS).

Is it a safety issue to have fonts that are optimized for viewing on electronic displays? I'll let you be the judge of that.

I will however give a personal opinion about Sans-Serif and Serif, with particular reference to the 3 font examples I used Earlier.

( An Aside: Sans is French or Middle English depending on your opinion, but for arguments sake I'll say French and introduce another prefix 'Certaine' to mean 'some'. )

  1. DejaVu Sans Mono I would describe as Certaine-Serif
  2. Liberation Mono I would describe as Certaine-Serif
  3. FreeSans is Sans-Serif
To get straight to the point ... looking at the letter l in the word 'black' in font examples (1) and (2), it can be seen that those letters are not entirely without "finishing touches". In particular in DejaVu Sans Mono, there is a quite nice look about the letter l.

For my mind, font examples (1) and (2) represent a middle ground between a Sans-Serif and a Serif. They have some "finishing touches" that aid comprehension, so helping readers easily distinguish the number one from letter l and so on, but they stop short of being full Serif.

Note: DejaVu Sans and Liberation have fonts that do not include "Mono" in the label which are perhaps less fitting to the purpose of this article. I steered clear of those variants as I wanted to choose a variant with a larger spacing between characters.

Below I have simulated what I would do if somebody was to print off a finished document, that had been prepared in Word 2007, and I wanted to match a proprietary font.

The output of fc-match using the -a option will produce a list of possible replacements. Without the -a option just a single "best" match will be displayed.

Users of Open Source Office software might ask...
"should I use DejaVu Sans Mono or Liberation Mono or FreeSans for my electronic document?"

Users of Non-free equivalents might instead ask...
"should I use Verdana, or Trebuchet, or Arial for my electronic document?"

If you believe some of the research that is being published at the moment, then the answer in both cases is perhaps the former rather than latter option.

( The owners of the proprietary Verdana font, have commissioned some research that allegedly supports its use instead of Arial as being easier to comprehend.
A quick websearch should turn up some hits to that research, but bear in mind who paid for it when considering any conclusions )

Putting that in the terms I have used in this article, perhaps Certaine-Serif rather than fully "without Serif" might be a better choice

The push by proprietary software to get you to drop Arial, is in non specific terms saying that readability is improved if instead of using 'straight' Sans fonts, that have been widely used in electronic documents for the last ten years, you use Mono variants / humanist variants.

Just one observation regarding Verdana in particular ... there are some opinions about the size which might be worth considering, before Non-free folks commit to using it in text that will appear in document form and on a website.

The article in the link above is a couple of years old and so does not include DejaVu Sans and Liberation Sans for comparison. If you want to conduct your own up to date comparison then it should be pretty quick to do some "quick brown foxing" to test your own view on size and suitability :)

A note regarding the font used for the text of this article. I have relied on images to provide my examples, as they cannot be subject to 'font replacement' on your computer. In writing this article I have just accepted the default font setting of Blogger.

Do download the Pdf to get further examples that should also render faithfully regardless of your brand of computer.

Here are some font comparions which I ran again in 2011:

Above Gnome Specimen Font Comparison - Creative Commons CC-BY-SA

Final note: In the phrase "Without Flair" in the article title, I do not mean to be critical of DejaVu Sans Mono or Liberation Mono, both of which I believe to have some nice touches and have happily used for documents.