What programs dominate in printers
There are more and more graphics processing programs, from the most popular Photoshop to less known and free ones like Inkscape. Professionals usually use one or two proven programs, which translates into their high productivity.
In the work of graphics or DTP operator you usually need a program for processing vector and raster graphics. You can also include word processors, programs provided by print equipment manufacturers, to the pool of programs needed for such work.
Wikipedia about laser printing
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
Online printing
Online printers are gaining more and more supporters, not surprisingly when more and more commerce is done online. This is a very convenient solution, because you can immediately overcome mistakes made by potential customers when placing an order.
Often, they send a bad file in the wrong format, with the web printing this error is still captured by the script itself accepting the order. Of course, such printers also have their drawbacks, ie the lack of the possibility of an individualized approach to the client and his needs, unless we get a really good printing house.