Are you designing your own eBook cover? Great! Here’s how to choose a font for the title and other text on your cover.
(And BTW< this is not something that’s worth obsessing over. You have a lot going on right now – and obviously, your first concern needs to be writing a great eBook.)
The difference between a screen font and a print typeface deals with the intricacies of readability and the science of typography. A screen font is one that’s designed to work and read well from a screen, versus a typeface that is designed for print, and not to be read on a screen at all. It’s a common mistake to not realize the difference, and use a screen font on an eBook cover, and I’m not sure that’s a good idea.
I should mention that the very word “font” is actually only used to describe the set of files that compose a screen font – not the typeface that is meant for print. Typography geeks might get on your back about that.
Screen (or web) fonts are meant to be readable in reflowable text situations, and represent well in what are generally lower resolutions on a screen. These fonts have different spacing attributes, meaning the spacing between letters, between the “legs” of each letter, and any enclosed areas, such as the gap in the middle of an “A”. Screen fonts are also meant to scale well and look good at both large and small sizes without any sacrifice to structure and readability. Font files will contain different sets of the letterforms than a print typeface. You’ll typically find a bold version, an enlarged bold, etc. Italics are found less often, due to their typically poor visibility on a screen. There’s a great article about this subject here: http://www.sitepoint.com/anatomy-web-fonts/
Print typefaces are typified by greater complexity and customizability, so that a designer in full control of the printed object can manipulate a typeface to an amazing extent. Designers can treat type like a graphic object, even though that’s usually something that’s tough to pull off.
A big part of this entire debate – and yes, it’s still an open debate – is what’s known as kerning. Kerning refers to adjusting the spaces between letters and words. A typesetter can adjust the kerning in a word or sentence so that parts of the letter overlap into the space of the letter immediately preceding or following it. For a great illustration of this concept, have a look at this Wikipedia article: http://en.wikipedia.org/wiki/Kerning.
Because we don’t typically adjust kerning for screen text, each letter in a screen font has a pre-set amount of space that surrounds each letter. This is what’s known as “monospaced” type. In other words, a screen font is meant to be standardized so that no matter what letter falls after which, the font will remain readable and properly spaced. Some screen fonts have evolved to be able to be kerned, but it’s highly automated, and like anything that’s fully automated, there will be some areas that just don’t work precisely the way that we’d always like it to. Sort of like factory cheesecake. Still good, but perhaps not worth blowing your diet over.
It’s not true that all serif typefaces are really for print, and non-serif fonts are for the screen, because in the years since modern monitors first came out, fonts and typefaces have evolved both artistically and in terms of usability. We now see both types of type in both print and on-screen. But there can be dramatic results by manipulating little things like the extension on the cross of a “t”, for example, which helps letters fit in a way that makes good use of the space on the screen, and still looks natural. Some typefaces, like Times Roman, were designed for specific things, like newspaper columns, and there are sooo many much better choices for serif typefaces in books, documents and papers, that I’m amazed that people still use that font at all. Times Roman is like the Scottish Play – you just can’t say the name of it at certain parties.
It’s considered a major no-no to use a screen font in print. The end result is a font that is not kerned properly, meaning that there are uneven gaps between the letters, which if they are used for the title, is going to glare at you from smack in the center of the cover of the book. There’s also something called aliasing, which very simply means that the angled edges of a screen font can be artificially smoothed to appear softer on the eye. Again, this is one of those areas that can get thoroughly messed up if you don’t understand the finer settings of stuff like Photoshop. Simply taking a high-resolution typeface and shrinking it down will not adjust the resolution properly, making it look “jagged” and blurry. See here for another article with an excellent technical explanation: http://en.wikipedia.org/wiki/Spatial_anti-aliasing
Screen fonts also have different effects when justified, due to automatic kerning. If you align a paragraph to be justified using a screen font, the letters across the line will be aligned with even gaps from the outermost point of each letter, which means that if an “A” and a “V” happen to follow each other, there will be too much space between them. A print typeface will typically automatically compensate for this, making the line appear more naturally-spaced, and therefore lend itself to a more natural reading experience. You cannot always correct this with hand-kerning. And even if you can, it’s time-consuming.
No matter what, if I were you, I would not geek out too much about this issue. There is an argument to be made that using screen fonts for the design of eBook covers is totally appropriate, considering that they are not meant to be printed out – the covers, too, are seen only on a screen. But I must say that I’ve seen a lot of oddly-spaced type out there: it floats, strangely, like a ship that isn’t anchored properly.
I think it’s a style choice. Is it readable? Does it look professional? Does it clearly make readers understand what they’re going to get in this book? If you answer yes to all of those, then great. Trust your eyes and your instinct.