The portable document format, ie "portable" or better for exchange suitable document format is developed by Adobe in 1993 file format, which has gained considerably in importance with the development of the Internet. In addition to html is
the PDF the most used document format on the Internet. It is used by many companies for manuals and datasheets, but also governments and other organizations use PDF very often.
A PDF can contain texts, pictures, graphics as well as vector drawings or 3D objects. The advantage of PDF lies in the fact that there are display programs on every platform and normally the complete layout (arrangement of pictures, fonts, etc.) is displayed the same everywhere. PDF documents can also be encrypted and work with Digital Rights Management (DRM), which is why you can find PDF more and more often in e-book stores.
The standard viewer on Windows and Mac systems is Adobe Acrobat Reader. However, since security vulnerabilities have been discovered many times, one should possibly resort to one of the free alternatives.
Also for the creation there are quite a few programs, whereby also here Adobe with the Adobe Acrobat course sets the standard program. In addition to some commercial alternatives, there is for example a free alternative with OpenOffice or LibreOffice. Another possibility to create PDF documents are the so-called PDF printer drivers (for example Bullzip, Mac OSX is able to create PDFs per print dialog), which make it possible to create PDFs from almost any program.
Via Plugin (http://extensions.services.openoffice.org/project/pdfimport) OpenOffice.org Draw can also import and edit PDF files.