Last week, I spoke a bit about covers: how important a good one is and what goes into that.

This week, I’m thinking a lot about what’s under the covers. In other words, interior book design.

What do I mean by that, you ask? I mean, it’s pretty much words on a page once you get in there, right?

Wrong.

Interior book design is as important, if not more so, than cover design. Because although a poorly designed book cover can keep you from buying a book, a badly designed book interior can make you regret that purchase. And that’s much, much worse.

What makes for a bad interior design? Well, here we’re talking mostly about fonts. A lot of study has gone into how the brain processes what the eye sees and what the optimal conditions are for that. It’s why in newspapers you’ll never (unless they’ve got an inexperienced or just plain bad page designer at work) see columns more than about 18 picas (that’s three inches to the reader) wide.

Why?

Because it’s too hard on the eyes to read across much farther than that and then keep coming back to the start of the column, which will make you stop reading. Newspapers already have a hard enough time getting you past the first couple of paragraphs.

But books are wider than three inches… so, what’s the problem?

Here’s where knowing your audience and their reading style comes in.

In newspapers, space is at a premium and so is time. Space for the publisher (how much content can I squeeze into the least amount of paper?), and time for the reader (how quickly can I scan these articles?… I’m very, very busy). As a result, newspapers use smaller fonts and tighter leading (the space between lines) to increase quantity (think “all the news that fits to print”). But that crammed-together type is hard to read, so it fatigues the eye faster and must be in narrower columns.

With books, however, people are planning to read for longer periods. In this case, they can scan across a wider format, but other considerations need to be made.

Font size, for one. Leading and paragraph indents, for another.

In books, the size of the type needs to be larger (11 points in a trade paper, for example, versus the typical 10 or so for newspapers). And the leading needs to be airier (4 points versus only half a point in newspapers, to use the same example). First-line indents for both need to be just enough that they clearly indicate a new paragraph but not so much that they make the eye feel like it’s skipping like a broken record.

And, of course, all of this needs to be in a serif font like Garamond or Minion because the eye can’t read sans serif fonts (like Helvetica or Franklin Gothic) for long periods. That’s why newspapers use them for headlines and photo captions, for example, but not body copy.

Why do those little serifs make a difference? They help the eye glide from letter to letter and word to word like little air traffic controllers. Without them, the eye has to jump from letter to letter like it’s playing leapfrog. I don’t know the last time you played leapfrog, but as the mother of a toddler, I can tell you, it gets exhausting after a short while.

Speaking of exhausting, I’ll wrap this up before I bore you with too many technical details (I’m a designer, I could go on all day). Suffice it to say that we’re paying a lot of attention to these details in our books here at WMG, and I think you’ll start seeing what I’m talking about as we release new print books (such as the Coolhunting novella featured on our home page this week).

So, be sure to keep a fatigue-free eye out for them.

Allyson Longueira is publisher of WMG Publishing. She is an award-winning writer, editor and designer.