Computer input and output devices - Essay Example

Computer input and output devices Computer input/output is the sending and receiving of information between the computer and the external world normally the human using it. Input is the data communicated to the computer by its user or another operating system while output is the response that the computer gives to its user or another operating system. The interaction between the input and output devices is studied under a field of study called human-computer interaction. Input devices Every computer requires a keyboard for data entry both in numeric, alphabetic and symbol form.

Text or numbers being typed on the keyboard are directly displayed on the monitor of the computer. There are many designs of the keyboard depending on the manufacturer, but they all have letters, numbers and function keys for data entry. The data is converted into codes that are understandable by the computer and displayed in a format understandable to the user within a time frame of milliseconds. The mouse is used to select items on the monitor and has two buttons, scrolling wheel, and a laser sensor which facilitate movement and selection on the monitor.

The joystick is used for input of data mostly while playing games in the computer. Modern computers are fitted with a digital camera which has the ability of recording photographic images in a digital format. Images can also be entered into the computer through the flatbed scanner that converts printed media into digital format. The 3D digitizer is a modern input device that is used to record the X, Y, and Z coordinates of real objects by the use of light or sound sensor robotic instruments or sometimes a robotic pen.

The graphic tablet is an input device that inputs accurate information using a stylus that is used on a tablet. This kind of device is used for artistic data input. Computers are fitted with microphones internally or externally and can detect various verbal commands. Output devices Every computer has a monitor that is the primary output device, and it communicates with the user by displaying data in a user understandable format. Another commonly used output device is the inkjet printer that produces papers printed in different colors by means of a spray ink jet inside the printer.

An advanced form of a printer is a laser printer that prints different colors by fusing electrostatically charged toner. The laser printer has very high initial cost but has lesser running cost as compared to the inkjet printer. The drum plotter is also an output device that plots large scale drawings mainly architectural and engineering drawings. Recent technologies have led to the introduction of laser plotters that are an advancement of the laser printers and are capable of printing into rolls of papers.

Data projectors are a modern form of output devices and can be described as big monitors that are used for audience presentation. Speakers are classified as output devices since they communicate information from the computer to the user either in the form of warnings or music.