There are new formats to optimize your presence online. Since 2001 Google has been indexing approximately over 500 million PDF files . You may be confused as to how Google is able to rank these files. Google has the ability to index textual information from the PDF. Remember even Google cannot surpass password protected files. Therefore if the file is password protected then Google won’t be able to index it. Also, Google uses optical character recognition which in essence extracts textual information from images online.
Google treats PDF links like an HTML link therefore it passes the PageRank and other indexing signals within the search engine. Similarly to passwords, the PDF files cannot have a “no follow” tag because if not Google will not be able to index it properly.
When trying to optimize your presence on Google through PDF files a title is highly important in search results. To influence your title online, you will need to look at the two influencing factors: the metadata within the PDF and text of the links that highlight the PDF in a search engine.