Not only leaflets
Printing is not only printing leaflets, business cards or large banners - it also prints other, necessary materials such as: stickers, self-adhesive letters or labels. In principle, everything that comes out of the printing house can be included in the category of printing.
There are plants specializing in the production of only a specific group of printed materials: eg leaflets, or only large-format printing. However, this results from a simple thing: for every type of printing you need to have the right machine, and these take up space and cost a lot. That is why printing plants limit the amount of services provided.
About standards
Standards in every industry and business are important. 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. Specified in advance formats for printing leaflets and business cards, so that they are comfortable and as uniform as possible. Without standards, even leaflets could be completely unreadable and even repulsive.
Services for printer owners
With the owners of printers in mind, various forums and websites as well as websites are run. They can also use online guides, which contain useful information for them and trivia from the world of printing services. Such guides can also help when you first connect a new printer or make some improvements to its functioning. In contrast, discussion forums for printer owners become a place where they can exchange opinions about individual printing devices. On the Internet, there are also shops with printers and inks as well as printing accessories, in which you can purchase even the most unusual goods.