Pointillism - Printing with Dots
Pointillism is the art of painting using only dots. Newsprint and typewriter printing was developed using a series of dots as well. Stippling, or creating images using dots, is a cost-effective method of printing that has developed from an art that is the opposite of cost-effective (pointillism.) Most users will be familiar with the terms ppi and dpi, points per inch and dots per inch respectively.
While computers and computer images have their own ppi, printers have a separate but related dpi capacity, depending on their type and class. Since computers store data using binary, meaning either 0 or 1 (on or off in the case of the dots) dots are a good way to communicate letters and images.
Printers such as dot matrix printers use a series of vertically arranged pins on the printhead that translate to the paper, and produces dots that make up printed images. In this type of printer, more pins means more dots per inch, and a sharper image.