Imagine that we buy a monitor and its input does not match our video card, even though it has the same type.
That's why certain standards apply. In polygraphy and graphics, such standards also exist - appropriate definitions of CMYK colors - key for the appropriate color reproduction.
Without standards, even leaflets could be completely unreadable and even repulsive.
Laser printing is an electrostatic digital printing process.It produces high-quality text and graphics (and moderate-quality photographs) by repeatedly passing a laser beam back and forth over a negatively charged cylinder called a "drum" to define a differentially charged image.1 The drum then selectively collects electrically charged powdered ink (toner), and transfers the image to paper, which is then heated in order to permanently fuse the text, imagery, or both.As with digital photocopiers, laser printers employ a xerographic printing process. However, laser printing differs from analog photocopiers in that the image is produced by the direct scanning of the medium across the printer's photoreceptor. This enables laser printing to copy images more quickly than most photocopiers.Źródło: https://en.wikipedia.org/wiki/Laser_printing
First, important things were printed like books.But these are REALLY important, not some literature for the mob. Well, because the mob was quite illiterate at the time.
Then also such fiction was printed, meaning for the reading of the book.
Because you need to build brand awareness at the customer, i.e.printing and marketing is an inseparable couple.