The properties of fonts vary significantly depending on the settings used during the creation of a PDF file. This can affect your ability to edit text in the PDF file. In particular, PDF files that contain subset fonts can be problematic when last-minute edits are required.
Font embedding assists with accurately rendering a PDF file to screen or print. If you want to use a font when you edit a PDF file, the font must be installed on your system.
Three levels of font embedding are used in PDF files:
No embedding. Choosing not to embed fonts creates the smallest file size because the are not stored in the PDF. The tradeoff is that, depending on the fonts used, the PDF may have a different appearance for some users. When common system fonts are used (for example, Times New Roman, Arial, Times, Courier, and Symbol), the PDF looks very similar to the original since these fonts are installed on virtually every computer. If you use a specialty font that your recipients do not have installed, your document could look quite different from the file you designed.
Subset Embedding. Only the portion of each font used in the source document is stored in the PDF, namely the characters that are required to properly reproduce the original document. Since only part of the character set is included in the PDF, if you try to edit the PDF by inserting a character (for example, ‘X’) that was not used in the original document, the character is not inserted because it was not included in the PDF. The reason why people use subset fonts is that they want their file to look exactly as designed, while being as compact as possible - embedding an entire font can increase file size significantly.
Full embedding. The entire font is embedded in the PDF. This increases the PDF file size, but is the best option for editing text directly in the PDF since it guarantees that all the font is available.
TIP: To list all fonts in a PDF and their embedding method, Ctrl+D or right-click the Hand tool anywhere on the document, and select Document Properties. In the Document Properties dialog, see the Fonts tab.
To view the font properties of selected text in a PDF, right-click the Edit tool on the text, and choose Edit Properties. The Text Properties window appears. Information about font embedding is at the bottom of the window .