About DTP Operators
The DTP operator is a responsible person in printers, publishing houses and wherever materials are printed in large quantities, for the correct preparation of files that will be printed. The task is easy and simple in theory, however, one small error of the DTP operator and the circulation of several thousand copies of newspapers can be thrown away. In this work, many things may go wrong: change of paper for another, new printer with other inks, incorrect conversion of colors. There are also typo errors, bad placement of some element or just a few details. All this can end very badly and bring big losses - so it's work under stress and tension, because if something goes wrong it usually will be just for the DTP operator.
Home and Professional Printers
Who today does not have a printer at home. Their prices are becoming more affordable and operating costs lower. Multifunction devices offer increasingly larger scanning resolutions, less margin, larger formats, etc.
But still, such home printers are far behind the professional equipment used in professional printers. Not to mention the much larger range of techniques used, which have nothing to do with those we know from home printers. Printed roll, solvent, water, anhydrous - long to exchange. The quality of such printouts is higher, which entails the obvious higher costs of printing itself.
Laser printing in Wikipedia
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