The resulting file can incorporate an index

The resulting file can incorporate an index, external links to the internet, automated page numbering and a multitude of other facilities.For the person who wants to read the book they use a software system called Adobe Acrobat Reader. Adobe makes this software available for free and it is widely distributed and used. It is an excellent product which allows the reader to print, use the index, and have complete control over the size of the text. It also facilitates add-ins such disability facilities (i.e. a synthesized voice system can read the text). The free Adobe Acrobat e-Reader system is an alternative to Acrobat Reader. As well as all the features of Acrobat Reader the e-Reader system takes any existing PDF file and presents the text in an e-Book form.The resulting PDF file is almost always far smaller than an equivalent executable file. Thus download times are shorter and the China 5 PU Leather Notebooks Factory file occupies less space on the reader's computer. PDF files can be guaranteed virus free, where as executable files don't have this advantage. People generally don't like to download files that have an exe suffix in the name. 

Exe files are a notorious way for viruses to be spread and people tend to be more reluctant to download them than they would with PDF files.PDF files have the advantage that they are supported on a variety of computer operating systems including all versions of Microsoft Windows, Macintosh OS, and Unix/Xenix/Linux. Exe files are restricted to Windows. And when you think for example that there are over 8 million Macintosh users in the US alone that's a large number of potential readers to exclude.Advantages of EXE files include:E-Book compilers are priced far lower than Adobe Acrobat Writer (around US$250). Such software is also far simpler to use. (Adobe Acrobat Writer is a very sophisticated publishing system with the creation of PDF files a minor function). There are other software products which can create PDF files. Some word processing systems have the facility, as does Corel Draw.Some e-Book compilers are available for free use. 

Those I've tried though all either add some information about themselves into the resulting document, or limit the number of pages. Alternatively they're limited to a trial period such as 30 days. The writers of such software understandably really want you to buy their software! Once purchased all these frustrating limitations disappear.E-Book compilers also (usually) include a rebranding facility. The rebranding facility allows other people to market your e-Book. But rather than having the contact details and web site links referenced back to your site, they can be altered to point back to their own site which the rebranded book promotes. Your authorship is still protected, but this feature allows the e-Book to be used in an affiliate program. The rebranding can be achieved with Adobe Acrobat Writer but it is more difficult to achieve.Using e-Books as a promotion tool is usually far more effective if the down stream resellers can customize the book to their own affiliate links.