Printers: Impact and Non-Impact Printers

These introductory lesson notes from Trinity College Nabbingo cover printers as computer output devices. They define a printer as a device that puts text and graphics onto physical media such as paper. Printers are sorted into two groups depending on whether the printing mechanism touches the paper. Impact printers strike a ribbon with pins or hammers, while non-impact printers form images using chemicals, lasers or heat. Examples are given for each group: character, line and dot matrix printers are impact printers, and thermal, inkjet and laser printers are non-impact printers. The notes end with a short summary and say that each printer type will be covered in more detail in a later lesson.