The buttons are used to select items and make choices on the screen. The mouse can significantly reduce user input by moving away from typing commands at the keyboard to clicking on buttons or other items displayed on the screen. You can learn more about the mouse here . Printer A printer allows the user to print out on paper a copy of the screen or the data that is being processed by the computer. Printers are available in both color and black and white.
Color printers are slower and more expensive than black and white printers.
In addition, the technology used to print the information on the paper varies upon the type of printer. You can learn more about printers here , and learn about the maintenance of printers here . Modem A modem is a device which allows the user to connect their computer system to another computer system. A modem attaches to a telephone line, and dials up another computer via the telephone. The modem converts the computer signals so that they work over the telephone circuits used by the telephone companies.