Portable Document Format (PDF) is a file format used to present documents in a manner independent of application software, hardware, and operating systems.
PDF File Format
Every glyf inside a PDF file can have a display value and a different extraction value. This is useful because often you need to... Text is defined in the PDF file format as a display value (normally what you see onscreen) and an extraction value. It is useful... What are PDF Xref tables? Xref tables are part of the original PDF file specification and one of the features which gives the PDF... Form XObjects (not be confused with forms which are buttons, checkboxes, buttons, etc) are an advanced feature of the PDF file format. They can... White is a special color in the PDF file format. This is because of the way different colours work in the PDF file format.... 
