PDF (Portable Document Format), is not just a well-known and convenient format, but the only one that has been standard since 2008. It was developed by the Adobe Systems team. The developers of the format set themselves the task of creating such a format for displaying the document so that the document opens and looks the same on any device. The PDF format is used for storing and transmitting text and graphic information on the network, for example, for transferring letterhead to the printing industry or posting a questionnaire on the website. Great for demonstrating developments: easy to show, edit - difficult. This complicates the theft of intellectual property. Well, the ideas of a "paperless office" are received with a bang by everyone who thinks about ecology on the planet.