Printers are output devices that convert the electronic information into hard copy and reproduce the output on a piece of paper. Scanners, on the other hand, are input devices that read information from a piece of paper and convert it into electrical signals. Both of these devices are electromechanical, meaning that they use electrical/electronic and mechanical parts to do their jobs. Here we will discuss some fundamentals of using printers and scanners and installing them, and take a look at the available tools to diagnose common problems.
Printers and scanners are available in different types and forms, with varying capabilities and pricing, depending on the technology they are built upon. In this section, we will take a look at the printing and scanning technologies, their components, and how they are connected to computers.
Laser printers use a sharp beam of light, the laser beam, to produce the text or image on paper. This is called the ElectroPhotographic (EP) process, originally developed by Xerox, and it is based on use of static electricity to transfer the ink, which is in the form of toner, to the paper according to electrical signals received from the computer. They are used for high-quality text and image printing, have faster speed than other printers, and have low cost of printing per page. Laser printers are known as page printers and their printing speed is represented as pages per minute (ppm).