Why are Accessible PDFs so much trouble?

PDF (Portable Document Format) was originally developed as an export option, just like a printer. It was a great way to "print" something to the screen and it maintained the look of the original document. Most times, PDF documents were created by scanning a paper document and saving it as an image file. Although some basic editing and commenting features were built into the professional Acrobat versions, it was never meant as an editing environment. In addition, when the PDF file format was introduced, the use of Assistive Technology to read a PDF was not available. Over the years, Adobe has worked to retrofit and develop the Acrobat programs to allow Assistive Technologies such as screen readers and refreshable Braille devices to utilize the products. Even with these changes, the true accessibility of a PDF document depends on how it is developed, converted, or edited.

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