Distributing your business's project proposal as a PDF enables any client with a free PDF reader to view it in the format you intended. Even if you don't have Adobe Acrobat or another PDF creation ...

A PDF is a suitable file format for creating and reading e-books. However, if you want to open an e-book in most e-readers, like the Amazon Kindle and B&N Nook, you must first convert it to an EPUB.