There are three possible ways that a computer's data is produced to communicate to the user. The most common one is through the monitor, which every computer must have. The other two ways are through sending information to a printer and voice synthesis.
The monitor display is also known as the visual component of the computer system. Early monitors were called video display terminals, or VDTs. It is the fastest and easiest method for viewing information. Output from computer memory or central processing unit is binary. It is converted into the chosen language and displayed as such. A monitor is the ‘endpoint’ of that conversion.
Beginning in the 80s with the introduction of personal computers, video cards in computers drove cathode ray tubes (CRTs) which are what displays the images, text and color on a monitor. Now, Liquid Crystal Displays, or LCDs have been most commonly used, displacing CRTs in today’s technology. This type of monitor can display higher resolutions than CRTs. It can also come in larger sizes. LCD monitors are composed of two plates of polarized glass, pressed together. There is a liquid crystal material between the plates which responds to electrical currents, allowing different wavelengths of light through the surface. The entire premise of an LCD monitor is to block out the majority of light. It only shows specific wavelengths, interpreted as colors. A backlight emits light, covering the entire back of the monitor, at all visible wavelengths. Behind the monitor's face, in front of the liquid crystal are transistors connected to pixels on the screen. It appears as transparent, but when varying currents runs through it, the pixels light up. This adds definition to the overall color, passing through from the backlight.
Next to monitors, the computer peripheral which is always used is the keyboard. The monitor works with it and the mouse when interacting with computers. They are the parts that move along with the use of multiple computers. They are the main network of the computer’s function.