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
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.... This is part of a series on How to make your own PDF files. In the previous article of this series, we learn to... 
