ARCHIVED: In Mac OS, what are the differences between PostScript Type 1 and TrueType fonts?

Although PostScript Type 1 and TrueType fonts are licensed for use with multiple computing platforms, this document describes the differences between the two font technologies in Mac OS. This document was also written primarily for Mac OS 9.x and earlier. Though it applies in general to Mac OS X, some of the details are different. For example, in Mac OS X, fonts of different types don't have different icons. Also, Mac OS X supports several font technologies other than the ones mentioned here.

PostScript Fonts

To render typefaces, PostScript fonts use Adobe's PostScript computer language. PostScript fonts can be resized, stretched, and distorted freely in illustration and page layout programs while maintaining smooth printed output on PostScript laser printers. PostScript fonts were the first to be used in desktop publishing, and are still preferred by many printing service bureaus for output onto very high resolution printers.

To work properly within Mac OS, a PostScript font requires three parts:

1. PostScript printer font: Often, this type of font appears as a red capital A with horizontal lines in the background or as an icon which looks like a printer. Double-clicking a PostScript printer font in the Finder will produce a help message telling you the font should be placed in your Fonts folder. A PostScript Type 1 font can be installed on a PostScript printer itself, eliminating the need to download font information to the printer when printing. PostScript printer fonts are not stored in font suitcases (the containers into which Mac OS groups bitmapped and TrueType fonts).
   
   
2. Screen font: A screen font is usually used only to display a font on the computer's screen, and is a bitmapped font of a single point size, with an icon displaying a single capital letter A. Screen fonts can be double-clicked in the Finder to view a sample sentence, and multiple point sizes are usually stored in a font suitcase.
   
   
3. Adobe Type Manager (ATM): Adobe's ATM control panel scales PostScript fonts to any size for on-screen viewing. However, ATM does not eliminate the need for screen fonts. PostScript fonts still require a screen font in order for the computer to recognize that the font exists on the system, and the more sizes of screen font that are installed, the faster ATM can render various sizes of on-screen type. In addition, ATM also allows PostScript fonts to be printed smoothly on non-Postscript printers. ATM is not necessary in Mac OS X.

TrueType Fonts

TrueType is a font technology developed by Apple, meant to compete with PostScript Type 1. As with PostScript fonts, TrueType fonts can be freely manipulated in illustration programs without a loss in printed quality. TrueType is only a font technology, however, not a complete page description language as PostScript is. TrueType fonts contain all point sizes in one font, and do not require separate screen fonts or ATM, but as with ATM, screen fonts are installed to speed up on-screen rendering. These corresponding screen fonts are usually stored in the same font suitcase with the TrueType version of the font. TrueType fonts can be distinguished by their icon, which displays a capital A fading backwards. Double-clicking a TrueType font's icon in the Finder will display 9, 12, and 18 point samples of the font.

Also see:

• Where can I find Adobe phone numbers and customer support contact information?
• In Mac OS X, how do I install fonts?