A friend of mine what to put her book online or offer it online. She mentioned doing it in PDF format but I'm not sure this can be done without allowing people to make multiple copies. Can you prevent people from making copys of a PDF file with Adobe products?
This is what products and service like ADEPT (http://www.adobe.com/products/adept/) are for. However, the entry price might be a little steep. Essentially, the answer is no, you can't prevent people from copying the PDF - it's just a normal file after all. All you can do is prevent people who aren't allowed to open the file. This is what the encryption is for (in part). But the trick is to somehow provide each valid user with the appropriate key to open the book. This can be done one by one in Acrobat with the password feature. Or one can use ACS (Adobe's DRM system) but that has been discontinued. Or, one can use ADEPT.
Thanks for the information. How do i find out more information about this product and how it works?
I would like to know if PDFs can be downloaded on to a computer or whether there is a time limit on the use of the file. Basically how does the file go from the publisher to the user? What happens so that the user can continue to reference the file? What happens, if he buys a new computer? Reinstall Windows or Formats his hard drive? How does this software prevent pirating?