Why Should I Use an Impact or Dot Matrix Printer
Impact printers, whether they use dot-matrix technology that uses small pins or daisy-wheel technology that uses a wheel with pre-formed characters like a typewriter, all work by having an element physically strike the paper. While impact technology has some serious drawbacks, including low-quality reproduction of graphics, slow printing speeds and high levels of noise, it also has meaningful advantages, making it especially useful in businesses that need to use self-reproducing forms or forms printed on continuous paper
Most dot-matrix impact printers use a tractor feed mechanism. Tractor feeds use wheels with sprockets that fit into strips with holes that are attached to the side of a regular size piece of paper. Because they feed the paper as a strip, impact printers work especially well with continuous feed forms and papers. While continuous-feed paper has the disadvantage of having perforated edges that can be unattractive, it also offers the convenience of being able to be connected to the printer where it feeds through hundreds or thousands of pages with less of a risk of jamming and without needing to be refilled.
Multi part Forms
Multi part forms consist of multiple copies of a form that are sandwiched together with either carbon paper or a layer of carbon contained in the paper. They can create automatic duplicates as long as the paper gets struck, transferring the carbon to the page behind it. Many businesses have impact printers solely because they work with multi-part forms.
While daisy-wheel printers product typewriter-quality output, dot-matrix printers use a column of small wires to create images. These wires, which are typically relatively thick, produce output that shows the individual dots that make it up. While dot-matrix output is somewhat ugly, it has a unique retro feel to it that can be desirable in some settings. It is similar to the digital clock effect in that it shows broken up characters, albeit broken up into dots instead of into segments, making viewers more aware of the underlying technology.
Finally, impact printers can be useful if you are extremely concerned about your privacy. The US government works with printer manufacturers to have their printers print pages with special hidden patterns of yellow dots so that they can be identified by law enforcement agencies. Impact printers predate this technology, making it much harder for the government to identify that your printouts came from your printer and enhancing your privacy.