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
Why are Indexed Colorspaces useful? Indexed colorspaces are very useful if you only have a limited number of colors in an image. If you... As mentioned previously the PDF format contains blend modes, a set of functions determining how overlapping objects on a page interact with the objects underneath... The PDF FIle Format includes some very sophisticated features. One of the most interesting ones is the Blend Mode (introduced in PDF version 1.4).... Did you know that the second line of the PDF is a set of characters to make sure PDF files are treated as binary... Using the HTML5 File API to validate PDF Files Recently in my own time I have been familiarizing myself with the HTML5 File API.... 
