The Appellate Record : Texas Appellate Lawyer & Attorney Kendall Gray for Fifth Circuit & Supreme Court Appeals

From Matthew Butterick

Windows and Mac OS X take different approaches to rasterizing. OS X uses a "smart rasterizer, dumb font" approach: the rasterizer makes all the decisions about how to draw the font. Windows, on the other hand, uses a "smart rasterizer, smart font" approach: fonts on Windows can contain extra software code called hinting that tells the rasterizer, sometimes in great detail, how to draw the font. If there's no hinting in a font, the Windows rasterizer will just make its best guess. If the OS X rasterizer encounters a font with hinting, the hinting will be ignored.

(If you're glazing over, it's not too late to turn back. The short answer is accurate.)

Over the years, Microsoft has released a series of heavily hinted fonts that are optimized to work with the Windows rasterizer. These include the aformentioned Georgia, Verdana, Calibri, and Cambria. So if you're using the Windows rasterizer — i.e., reading documents in a Windows word processor — then these fonts look best. Below is a screen shot from Word 2007 comparing Cambria and Georgia (two screen-optimized fonts) with Sabon and Quadraat (two print-optimized fonts).

How about on the Mac? Most Mac users also have these Microsoft fonts installed. Are they superior to other fonts for screen use? No. What makes these fonts work well in Windows is the hinting. The Mac ignores all the hinting. If you're on a Mac, you can use the Microsoft fonts if you like them, they don't have any special screen advantage over others.

Which brings us to PDF. Rather than rely on the Mac or Windows rasterizer, Adobe outfits its Acrobat products with its own font rasterizer. Why? Adobe wants Acrobat to display PDFs the same way on Windows, or OS X, or wherever. When you're seeing fonts in PDF, the Adobe rasterizer is doing the work, not the Windows or OS X rasterizer.

The Adobe rasterizer's approach is more similar to OS X than Windows. Like OS X, the Adobe rasterizer ignores the hinting in fonts like Georgia, Verdana, Calibri, and Cambria. So in PDF, these fonts look no better or worse than any other font. Here's the same text sample as before, but using Acrobat on Windows rather than Word 2007. 

With the Adobe rasterizer, Sabon and Quadraat look a lot better — certainly no worse than the putatively screen-optimized fonts, Cambria and Georgia.

"If screen-reading considerations are equal, then why not prefer the Microsoft fonts in PDF too?" Because printing is the tiebreaker. One of the benefits of using PDF is that your recipients have the option to print it, and sometimes they will. Those special Microsoft fonts — Verdana, Georgia, Cambria, Calibri, etc. — just don't print that well. Therefore, in PDF, your best bet is to use your favorite print-optimized font. Whether the recipient reads it on screen or prints it, you're covered.

"If I use my favorite print-optimized font in my PDF, how will the recipients see it?" When you make a PDF, your fonts get embedded in the document and travel with it. That means that even if the recipients don't own the same font, they'll see your formatting accurately. For example, I reformatted this Texas Supreme Court opinion for a prior blog post using the font Miller, which you'll see even if you don't have it on your computer.
 

From Kendall:

So there you have it, the whys and wherefores of why PDFs are going to look great so long as you choose a great font. Huge thanks to Matthew Butterick for again agreeing to a guest spot on the blog. If you enjoy this kind of topic but haven't yet got his book, Typography for Lawyers, you are totally missing out. Get on it!