Typography 101

Typography is the study of type, meaning letter forms of the printed word; though in modern usage it includes all manner of non-printed letter forms such as computer screens, eBoors, electronic billboards, and even textiles. Typography is possibly the most important part of design because humans are visual creatures and nothing conveys more information in a smaller space than words. This article will cover the basic terms and anatomy of type, then give you some quick tips to help choose fonts wisely.

this is my text inside of a figure that is going to be on the side. I hope that it works!

Unlike my last topic, color, modern typography is actually quite old. Most of modern color theory was developed in the 20th century with the invention of modern dyes, paints and emissive displays. The core typographic theories, however, were in place when Gutenberg made the first printed books over 500 years ago. Certainly a lot has been developed since then, but the universal principles of type like alignment and grids were already developed during the dark ages by monks transcribing bibles by hand. When Gutenberg converted these principles to his mechanical printing press modern typography was born.

Typeface vs Font

A typeface is a set of fonts designed with a stylistic unity, each comprising a coordinate set of glyphs. (wikipedia.org)

First things first: typefaces versus fonts. A typeface, also called a font family, is a set of fonts designed with a stylistic unity, each comprising a coordinate set of glyphs. (wikipedia.org). A font is a complete character set of a typeface at a particular size, weight, and style. In software engineering terms you can think of a typeface as a class and the font as an instance of that class with a particular configuration.

The exact meaning of typeface and font have changed subtly over the years as the technology has shifted from mechanical type to computer-set type to purely digital type. Originally fonts from the same typeface were literally different boxes full of chunks of metal shaping each letter at a given size. These days we have scaleable font technology so different sizes, weights and styles can be generated algorithmically or the multiple forms can distributed in a single physical file. Thus font and typeface have somewhat merged, and today you can safely refer to a typeface as a 'font' in general usage, and only use the more precise terminology when referring to particular instances of that font (or when talking to ornery typographers).

Anatomy of a Font

Weight

Helvetica (wikipedia.org)

The weight of a font is the thickness of the lines that make up the letter forms. Since this thickness is relative to the size of the letters we refer to these as their weight. You are probably most familiar with bold vs regular, but some fonts have as many as nine weights from thin and light up to bold, heavy, and black. The True Type font format specifies weights on a scale from 100 to 900. CSS can use words or scale numbers to specify the weight.

Style: AKA Slope, Italic & Oblique

roman, italic, and oblique (wikipedia.org)

We usually think of the slope of a font as italic or normal but, as with everything in typography, there's more subtlety to it. Italic text really means text which is drawn differently to indicate it is emphasized and should stand out in some way. Italic text can be programmatically generated by leaning the text to the right, called oblique text. Some fonts include a true italics form which actually draws the letters with different shapes. Fancier fonts may lower the fs, adjust the roundness of letters, or lean to the left instead of the right (depending on the language).

Width

Some fonts have wider and narrower versions of the letterforms. The terms for these versions vary by font maker, but will often be called things like condensed and expanded. These fonts adjust the horizontal width of the letters themselves.

Leading

Leading (pronounced like treading or fed-ing) is the spacing between lines of text. Back in the metal typesetting days they used strips of metal lead to separate lines, which is where the name comes from.

Kerning & Tracking

Kerning and Tracking (wikipedia.org)

Keming, from Ironic Sans.

Kerning and Tracking are adjustments to the spaces between letters of a proportional font. With tracking the extra space uniformly applied to all letters. With kerning the extra space allocated by letter pairs. This means that certain pairs of letters will have more or less space than other pairs, resulting in a more pleasing look. In some cases letters may vertically overlap to make them look better.

Kerning values are very hard to generate algorithmically because it depends on the how the letter forms visually look to the human eye. For this reason well kerned fonts are created by hand by a font expert, and are therefore more expensive. The results can be well worth it, however, because the badly kerned fonts result in keming. Also available as a T-shirt.

Font Metrics

Font Metrics (wikipedia.org)

The actual letter forms have a specific vertical anatomy based on how we measure them. Together these measurements are the font's metrics. We use these measurements to decide how to put letters together to form words, lines, and paragraphs of text.

Of the various measurements in this diagram the most important is baseline. The human eye finds baseline aligned text very pleasing, and will notice the tiniest imperfections in this alignment.

In GUI software it is important to align UI controls containing text (which is most of the standard controls) along the baseline of the text rather than the visual bounds of the actual control. For example, a button should be aligned with the text inside the button rather than the rectangular edges of the button itself. It may seem like a small detail but it makes a big difference. I once spent a year fixing bugs in the Windows Look and Feel for Swing, and the most visible bugs were vertical alignment issues. Yes, I spent a year of my life turning this:

into this

All in all, I still think it was a year well spent :)

Odds and Ends

Small capitals, aka: smallcaps, is simply smaller forms of the capital letters. Usually these smallcaps have the same height as the lowercase letters of the normal font. Smallcaps may be included in a font or generated algorithmically by shrinking the regular capital letters.
Dropcaps or Initials: special forms of the intial letter in a paragraph or chapter. They are often much larger than the regular text on the page and will 'drop down' into the lower lines.
Logical font: a font which doesn't actually exist, but will be replaced with a real font at runtime. For example, in webpage you can use the font 'sans-serif'. There is no real font named 'sans-serif', but the webbrowser will pick the user's preferred sans serif font and substitute it at runtime.

Categories of Fonts

In Roman languages (languages which use the 26 letters of the Roman alphabet plus various accent and punctuation marks) there are five major categories of fonts.

Serif

Serif Font

Serif letters drawn with features at the ends of their strokes. The serifs are the little feet we see in fonts like Times. These are some of the oldest type designs. The feet along the baseline help guide the eye from left to right, making them very 'readable' fonts.

Sans Serif

Sans-serif Font

Sans Serif (french for "without serifs") are letters drawn with straighter lines and no feet. Their larger letterforms make them very legible, but can cause greater eye strain when used in long runs of text. Helvetica is considered the quintessential sans serif font.

Script

Script fonts imitate hand written letter forms. They are much harder to read than serif and sans serif fonts, and should never be used for body text.

Ornamental

Type set in Baby Kruffy

Ornamental fonts are highly decorative and tend to work only at larger type sizes. They are often called 'display' fonts. They should never be used for body text (I'm looking at you, Comic Sans!).

Monospace

Monospace fonts have letterforms that are exactly the same width, or are at least equally spaced. These come from the days of typewriters and old computers that could only move fixed distances. The are rarely used today except when the vertical alignment of columns matters. Examples include code editors and laying out tabulated data.

Text Placement

Most of our type terminology in software comes from the world of newspapers. In practice we have three major kinds of text when building webpages and software: body, header, and navigation.

Body: this is the bulk of your text organized into paragraphs. It is usually smaller than the other text and should use a simpler font that looks good at smaller sizes.
Header: this text in short runs (usually a single line or less) that must stand out. Headers usually appear at the top of a page or paragraph indicating that the reader should move their eyes here to begin reading something. Headers also look good with serif and sans serif fonts, but you have more freedom because the text is typically larger.
Navigation: this text is very short and is usually at the top or sides of the page or screen. It indicates the structure of the entire work, such as newspaper sections or different pages in a site. It should also indicate to the user how to navigate to that section. In a newspaper you would use page & section numbers. For software the text would be rendered as something clickable (a button, an underlined link, a hover effect etc.).

Quick Tips

Use the right font for the size

Not all fonts look good at all sizes. Some really shine at small sizes, others at large ones. Use the right font for your size. At smaller sizes you want fonts which are simpler and easier to read such as the basic serif and sans serif fonts. Try Arial, Helvetica, Times, Verdana, and Georgia. They are installed on virtually all computers and were designed to look good on screen at smaller sizes.

Use different font categories for different parts of text

Use a sans serif font for the header and a serif font for the body, or vice versa. It creates a contrast without banging you over the head with it.

Use truly crazy fonts only for top headers

Home page of Project MaiTai

Use the cool and crazy fonts only for the top most headers. In the example below I used a font meant to evoke mid-century Tiki-culture, with a funky light effect to suggest it's alcoholic origins. I only used this font in one place: the top most header of the page. Everything else is done with Helvetica; a standard sans-serif font.

Use restraint. Pick one crazy font to use for your whole site or application and use it sparingly. If everything is different then nothing is. You can use a fancy font (somewhere between the plain boring fonts of body and crazy fonts of only top most headers) for headers within the page. And use one of the plain boring fonts for body text. Leave the crazy fonts just for the top most header.

Use color and style to create contrast

iTunes 9

Use color changes or capitalization style instead of fonts to contrast between the headers, body, and navigation. For example, in recent versions of iTunes the headers in the sidebar are all capitalized and in a slightly lighter color with a hint of etching.

Bundle a font in your app

For the body text I still recommend sticking with one of the standards, but for your header font you can choose something a bit more distinctive. Here are some great places to get cheap or free fonts.

Avoid Cool Fonts

Sniglet

Don't use cool / cute / themed fonts unless the subject matter really warrants it. Your website on technology trends really shouldn't use a cutesy bubble font unless you are really targeting the tween market.

Just the beginning

Typography is an incredibly large topic. What I've covered here is just the beginning. In the future I'll cover text as part of the overall design and dive into the grid system. If you'd like to read more on typography, here are a few good resources:

The Wikipedia page on Font
A List Apart on Web Typography.

20 Do's and Don'ts