Identifying Font Formats
If you've read this chapter from the beginning, you'll realize that not all fonts behave the same way. PostScript fonts, TrueType fonts, and OpenType fonts all have their own idiosyncrasies, not to mention some major functional differences. It's important to be able to tell them apart.
If you're looking in the folders where the operating system stores them, you can distinguish among the three formats relatively easily. Some applications display icons alongside the entries in their Font menus, but such displays are not standardized and not always perfectly clear. In general, it's better to know the formats of the fonts you use before you install them in your system and to create a method for keeping track of what's what. Fonts in different formats may appear with identical names in your Font menus, and having two such fonts listed side by side is something you want to avoid. Furthermore, it's entirely possible for an operating system to fail to distinguish between two fonts of the same name in different formats and to list just one of them in an application's Font menu. Not only won't you know that there are two fonts with the same name on your system, but you also won't know which one you're getting.
At one time, only OpenType fonts containing PostScript font data (so-called PostScript-flavored OpenType fonts) ended with the filename extension .otf. This is no longer the case. The .otf filename extension simply means that it is an OpenType font file that can be used on either a Mac or a PC. While TrueType fonts normally carry the filename extension .ttf, a TrueType font file that will work on either platform gets the .otf extension.
Fortunately, it no longer matters whether a given OpenType font contains TrueType or PostScript font data. Both work equally well on all computers and output devices, and all incompatibilities between the two ways of programming fonts have been ironed out. Nevertheless, if you want to, you can see what kind of font data a particular OpenType font contains. On the Mac, choose Show Font Info for a selected font from Font Book's Preview menu. On a Windows PC, this information is generally shown as part of the font file names in the Windows/Fonts folder. If this display is ambiguous, select the font file name and choose Properties from the File menu.
Identifying Macintosh Fonts
The Mac icon for an OpenType font is shown in Figure 4.10, both as it appeared before OS X 10.5 and after. Starting with OS X 10.5, all font icons show a small preview of the typeface itself.
Figure 4.10 Beginning with 10.5, Mac font icons display a sample of the typeface the font represents, as shown above. If you choose, will also display filename extensions, although this may not work on older PostScript fonts, as shown on the top here. Of these two Centaur font icons, the one on the left is the outline (printer) font, and the one of the right, its bitmapped (screen) complement. For more information about the format of a font file, select the file and choose Get Info from the Finder's File menu. In the Finder's large-icon list view of the same font files below, barely visible on the icons are the legends LWFN, FFIL, OTF, and TTF..
PostScript Type 1 fonts typically appear in Mac Finder windows without any filename extensions. That's because most of them predate OS X, which introduced the need for filename extensions on the Mac as a means of identifying file types. Using Get Info will reveal whether a font is a PostScript font. In the PostScript regime, each member of a font family is a separate file, so their names can become long enough that they have to be abbreviated into forms—such as OfficSerBooIta (Officina Serif Book Italic)—that may make them nearly unrecognizable. The weirdness of the names is often a giveaway.
In early versions of OS X, icons for PostScript fonts bore the label LWFN, short for LaserWriter Font (in homage to Apple's first laser printer). The icons of the companion collections of screen fonts were labeled FFIL (Font File). These can still be seen in the Finder's large-icon list view, as seen in Figure 4.10. The FFIL label may also be applied to TrueType fonts that include embedded bitmaps for screen display at particular sizes. In certain Finder views, a TrueType font may be referred to as a font suitcase, a term usually reserved for a collection of bitmapped screen fonts associated with a PostScript Type 1 font.
TrueType fonts are most commonly displayed in the Finder with one of two possible filename extensions. One is .ttf (TrueType font) and the other .ttc (TrueType Collection). TrueType Collections are single fonts that contain character outline data for several typefaces. The font AmericanTypewriter.ttc, for example, can generate type in six typefaces: Light, Regular, Bold, Light Condensed, Condensed, and Bold Condensed. The icon for such a font is a small preview of the regular roman member of the family.
If you use the Finder's List view instead of the Icon view, you will have to rely on the file names alone, as the tiny icons that precede individual file names are too small to decipher. If you opt for the Column view, you have the option of displaying a preview column that for any selected font shows a typeface sample in addition to information on the font's format.
Identifying the Formats of Windows Fonts
In versions of Windows prior to Windows 7, if you look at fonts in their folders, you'll see them all identified with unique icons that distinguish PostScript from TrueType from OpenType fonts (see Figure 4.11).
Figure 4.11 Versions of Windows before Windows 7 clearly identify the formats of all fonts. In the Fonts window at left, the large-icon view clearly marks the file icons with the that stands for TrueType, an for OpenType, or a lowercase italic for PostScript fonts. The icon with a capital indicates a bitmapped font. On the right, the view has been switched to Details, which explicitly lists each font's formats under the heading Font type.
In versions of Windows through XP, the filename extensions of font files are displayed in the Fonts folder. In later versions, only checking Properties in the File menu will reveal the filename extension. TrueType font names have the extension .ttf (TrueType font) or .ttc (TrueType Collection; a single font representing multiple typefaces), although these extensions can also be used for "TrueType flavored" OpenType fonts. As far as Windows is concerned, those formats are virtually identical, varying only by their character sets. Not all OpenType fonts, then, will have an .otf filename extension. Those that do will also work on a Macintosh.
If you're using Windows 7 or later, you should choose the Details view for the Font menu. Once you've turned on the option to display Font Type (by right-clicking in the column-titles bar) this view will show you each font's format plus other useful information. For most fonts you install, you can also right-click on their file names and select Properties from the pop-up menu that appears. This panel displays a range of information about each font. The Properties option is not available, however, for many of the fonts included with Windows 7.
PostScript Type 1 fonts have the filename extension .pfb (for the font files containing the character outline data; the b stands for binary) and .pfm (for the corresponding file containing the bitmapped screen fonts and metrics—that is, character-width—data). Because at the time of these fonts' manufacture most versions of Windows were based on DOS (disk operating system), the length of older font file names were limited to eight characters plus a filename extension (after a punctuating dot) of three more characters. This makes the names of most PostScript fonts completely unintelligible. It's not apparent, for example, that VARG____.pfb is actually Viva Regular. Fortunately, when they're placed in the Windows/Fonts folder (where installed Windows fonts are normally stored), Windows reads the true name of the typeface from within the font and displays it in readable form. In addition, it's common for Windows applications to indicate in their Font menu the formats of the fonts listed. Here, ideally, is where you want to know this information, and it would be preferable if all programs on all platforms performed this useful service (see Figure 4.12).
Figure 4.12 The Font menus of Windows programs often identify the formats of fonts with small icons. In this window, Windows Notepad distinguishes between TrueType, PostScript, and OpenType fonts in its scrolling font list. The Windows system's bitmapped Modern font appears without an icon.