The type of font you use can affect how text in your PDF files appears and prints, and whether or not the text is searchable and editable
If a PDF file contains fonts that have been converted to bitmap images, the viewers won't process the images as fonts, but will instead display and print the images just like any other bitmap images. Text converted to bitmaps, however, isn't searchable or editable.
dFonts (Mac OSX only)
These fonts are native to the Mac OS X system and are identical to standard font suitcase files except that the font resources are stored in the data fork of the file. Acrobat Distiller handles dFonts the same as other TrueType fonts on Mac OS.
You can create PDF files that contain Kanji fonts using both Kanji and English-language versions of Acrobat Distiller. (For English-language versions of Acrobat Distiller, you must install the appropriate font support package.) Acrobat automatically displays Asian fonts that are embedded in a PDF file. If Asian fonts aren't embedded, Acrobat can display them after you install the appropriate font support package. For information about installing font support packages, see document , "Viewing and Printing Asian Fonts in PDF Files Using Roman Acrobat Viewers."
Multiple Master (MM) fonts
Because multiple master fonts (such as Minion MM) create specific instances of a font based on the properties of a document and where the font is used, Acrobat Distiller cannot embed them. Instead, Acrobat Distiller adds a subset of the font, which has a unique font ID. Because MM fonts generate these instances dynamically, you cannot embed the fonts or edit them in Acrobat. Adobe Technical Support recommends that you don't use MM fonts if you need to edit or embed fonts in Acrobat. For more information on MM fonts, see document 328600 , "Multiple Master Fonts General Information."
OpenType Fonts from Adobe
OpenType format is based on Type 1 and combine outline, metric, and bitmap data into a single font file. OpenType format includes advanced typography features that most applications have not yet taken advantage of; as a result, these applications recognize and treat OpenType format as TrueType fonts. This treatment affects the way OpenType Fonts from Adobe are embedded in PDF files. Type 1 font embedding requirements apply to Type 1-based Open Type Fonts from Adobe. TrueType embedding requirements apply to TrueType-based OpenType fonts.
You can embed OpenType Fonts from Adobe in Acrobat Distiller 7.0 if you select PDF 1.6 compatibility, however the OpenType-specific features will be available only in Acrobat 7.0. (Choose Settings > Edit Adobe PDF Settings, click the General tab and choose Acrobat 7.0 (PDF 1.6) from the Compatibility pop-up menu.)
Because each symbol font contains unique characters and character sets, Acrobat Distiller always embed these fonts to prevent them from being substituted.
TrueType fonts that have installation and editing permissions can be embedded in a PDF file by Acrobat Distiller. If the font doesn't include these permissions, Acrobat Distiller embeds a font subset (that is, only the characters of the font that are used in the document).
Note:Acrobat Distiller doesn't report subsets of TrueType fonts in its log file. And even though the TouchUp Text tool in Acrobat lists the fonts as embedded in the Text Attributes dialog box, you cannot edit a font subset with this tool because the system can't recognize the font subset's unique font ID and map it to the original TrueType font on the system. If you edit a font subset with the TouchUp Text Tool, Acrobat substitutes the font with a sans serif or serif equivalent.
When you use Acrobat Distiller to create PDF files, text formatted with TrueType fonts may not be searchable, depending on how the font information was written into the PostScript file. In these cases, PostScript printers convert the TrueType font as a Type 42 font, which best preserves the font's characteristics, such as searchability. The Type 42 font format exists primarily as a way for PostScript interpreters to download non-PostScript (TrueType) fonts. A Type 42 font consists of a PostScript language "wrapper" around a TrueType font. A Type 42 font is usually generated by a printer driver to download TrueType fonts to a PostScript printer that includes a TrueType rasterizer. By this method the TrueType font is interpreted directly by Acrobat Distiller, which provides the most accurate description of the original TrueType font. Variables that can affect this font information include: the application that created the PostScript file, the font itself, the PostScript printer driver, and the PostScript Printer Description (PPD) file. If text formatted with TrueType fonts is unsearchable in a PDF file created with Acrobat Distiller, change one or more of these variables and then re-create the PDF file.
Information is written into a PostScript file either by the application that generates PostScript code or by the PostScript printer driver. For more information, see that application's documentation, or see "How Postscript Printer Drivers Handle TrueType Fonts in Windows" in this document.
Type 1 fonts
For both appearance and searchability, Type 1 fonts offer reliable conversion to PDF. Because Type 1 fonts don't need to be converted to another format when the font (or a subset of the font) is embedded in a PostScript file, they offer the best results when you use Acrobat Distiller.
To embed Type 1 fonts, the following conditions must be met:
1. In the Adobe PDF Settings dialog box, the font appears in the AlwaysEmbed list in the Fonts tab and EmbedAllFonts is set to True.
2. No symbols are used (except the symbol for pi).
3. The font size is within an appropriate range (this is, the CharStrings dict leng value is greater than 115 but less than 229). You can check the CharStrings dict leng value in a font editing application.
Type 3 fonts
Because Type 3 fonts use the entire PostScript computer language to express a font, they can include specifications that Type 1 fonts cannot, such as shading, color, and fill. However, Type 3 fonts aren't optimized for size or performance, so characters may appear bolder than their Type 1 counterparts.
Type 3 fonts are always embedded in PDF files, so they're always available in Acrobat or Adobe Reader (except on Mac OS X, which doesn't support Type 3 fonts). Acrobat and Adobe Reader convert the Type 3 characters to bitmap images and then display them. When you print to a PostScript printer, Acrobat and Adobe Reader use your PostScript printer driver to download the font to the printer. When you print to a non-PostScript printer, the bitmap images print. Type 3 font characters in the ISO Latin 1 character set convert to searchable text in PDF files, although those in the symbol character sets do not. PDF files with embedded Type 3 fonts usually have larger file sizes than those with embedded Type 1 fonts.