This piece is to serve as a quick note on figures: What they are, and when and how to use them. My Belgian counterpart, Yves Peters, has already written a much deeper and more comprehensive look into figures, two in fact, that I hold up as a reference. I’ll try to keep my own comment on the subject as short as possible in order to justify its existence.
Figures are to numbers what letters are to words. Just as lowercase letters range above and below the x-height and baseline of a typeface, ranging figures – or text, lowercase, or old-style figures (these are synonymous terms) – have ascenders and descenders. This formal quality of the figures gives them the ability to blend in with a body of text with minimal disruption, leading to better color on the page and arguably a better experience for the reader.
Lining figures, often the default, are full cap height. These work best with all-caps settings.
Tabular figures are for setting information in rows and columns. The word tabular refers to the figures’ spacing. They’re all the same width. When it’s desirable for figures to align vertically, say, in a list of telephone numbers or an actuarial table, the figures’ common width allows this. Tabular figures can be either lining or old-style. At the time of this publishing, March 14, 2013, the blog’s body copy is set in FF Milo Serif Web, which defaults to tabular lining figures, as do all Web FontFonts. Figures that aren’t spaced to a common width are generally spaced proportionally.
There are more. Often, a face that includes small caps will include one or more sets of figures sized to fit specifically with its small caps. Super- and subscripts, also called scientific superiors and inferiors are also common, usually either lining or ranging, rarely both. The same is true of fractionals, or numerators and denominators used by OpenType to create arbitrary fractions. As a rule, numerators set slightly lower than superscripts, denominators slightly higher than subscripts. Some faces, such as Nick Shinn’s Scotch Modern, highlighted yesterday in Great Pairs, have an additional set of numerators and denominators for setting what are called nut fractions, the kind you likely wrote when first studying fractions. When appropriate, special punctuation, mathematical operators, currency symbols, etc. are included in a font to work with these additional sets of figures.
I could add here that not everything fits neatly into the above classifications. Uncommon figure sets such as Bell’s or Miller’s three-quarter figures stand between cap-height and x-height. Note how Miller’s range slightly. Also note how occasionally lining figures range slightly, such as in MVB Verdigris. Yves documents more uncommon figure conventions in his piece.
Lastly, there’s no guarantee the set of figures you need exists in the typeface you need to use. Prior to OpenType, meaning just about all fonts produced before the mid-1990s, designers had to license additional fonts should they need the added flexibility of multiple figure sets. This is why on FontShop and elsewhere you’ll occasionally see products marked LF or OsF. These fonts differ only in the figure style included, whether lining or old-style figures.
Next week we’ll talk less and get our hands greasy setting all these. Using Type continues here Thursday.