Computer input and output devices are devices that facilitate communication between a computer and the user of the computer or another computer. Input and output devices allow users to interact meaningfully with a computer. There are many types of common input and output devices that users rely on in every day computer use.
Pointing devices are computer input devices that allow the user to move the onscreen pointer and select and control objects on the screen. Computer mice are the most common type of pointing device. Other types of pointing devices include trackballs and touch pads. Trackballs are similar to standard ball mice except that the ball is rotated by the thumb rather than by moving a mouse across a surface with the hand. Touch pads allow the user to control the pointer by dragging a finger across a sensitive pad. Joysticks and game pads are other types of input devices.
Keyboards are another common type of input device. Keyboards allow users to input characters such as numbers and words as well as key commands that can carry out various actions on a computer. Many of the actions that are normally carried out with a mouse can be performed with a keyboard by using the appropriate key commands.
Monitors are output devices that display a visual interface which allows the user to interact with a computer. TVs can also act as output devices and many computers can output video information to more than one screen at the same time.
Speakers are devices that allow for audio output. Audio output is not essential for many of the basic interactions users have with computers, but audio prompts can help call attention to certain events and computer audio is used extensively for entertainment.
Microphones are audio input devices. Computer microphones can be used to record sound as data onto a hard drive or to communicate with others over the Internet using voice chat or video chat software.
Printers and Scanners
Printers are peripheral devices that facilitate the output of text or images on paper. Scanners perform the opposite operation, facilitating the input of information on physical documents into a computer. Many printers are all-in-one devices that have both printing and scanning capabilities.
Webcams and Digital Cameras
Webcams are peripheral computer devices that can record video and take photos. Webcams can be used to for real-time video conferencing using programs such as Skype, Oovoo and Google video chat. Digital cameras and camcorders can be connected to computers, often through USB ports to input and output images and video files.