Input and output devices allow users to interact with computers. Input devices, like keyboards and mice, allow users to enter data. Keyboards contain standard keys and come in wired or wireless varieties. Mice control on-screen pointers and come in digital, analog, or mechanical forms. Scanners capture images and microphones input audio. Output devices, such as monitors, printers, and speakers convey information. Monitors come in LCD, LED, or CRT varieties. Printers include dot matrix, inkjet, laser, line, and thermal printers.