What is a Dot Matrix Printer?

Dot matrix printers normally have 9 or 24 pins arranged in the form of a matrix as show in the image bellow. To print a character on the paper, the built-in microprocessor activates the appropriate pins in the print head to move forward and hit the printer ribbon, which is placed against a paper. As a result, the shape of the character appears on the paper. Dot matrix printers form the shape of characters by a number of dots and not with the character shape itself; therefore the print quality of these printers is low.