Summary
Highlights
Dot-matrix printers create output using a matrix of pins that press against a ribbon to mark paper. The printed characters are formed by small dots. They are ideal for carbon copies due to their impact mechanism and offer a low cost per page but are noisy and produce low-resolution output, making them less common for general home or business use.
The print head moves back and forth across the page, with small pins inside that press onto an ink ribbon, transferring ink to the paper. The print head is relatively small and gets warm, often having a heat sink. To print a full page, the print matrix moves across and the paper advances for each line.
Dot-matrix printers use a single, continuous ribbon cartridge that stretches across the page. This ribbon cycles through the cartridge repeatedly until replaced. Replacing cartridges is easy but requires finding the correct size for the specific printer model. The ribbon inside is a long piece that collapses and extends as needed.
Tractor feed systems use holes on the sides of paper to pull it through the printer, ensuring straight alignment. Misalignment or missing holes can lead to paper jams. This type of paper, often called 'tractor paper,' can be a continuous roll or perforated into standard-sized sheets. Some also have perforations to remove the tractor feed edges, and 'green bar paper' is a common type used for programming output.
Dot-matrix printers are suitable for multi-part paper, allowing multiple copies from a single pass. Traditionally using carbon paper, a more modern method uses micro-encapsulated ink on the first sheet and clay on the second, which reacts to create the copy. These papers can sometimes cause skin irritation. Many organizations now opt to print multiple copies digitally, finding it less expensive and simpler than using multi-part paper with impact printers.