The CRT monitor was one of the most common computer monitors up until a few years ago. Today it is loosing more and more ground to new and technologically improved monitors like the LCD(Liquid Crystal Display) monitor which has climbed to the top of the computer monitor purchases. Despite this recent decline of the CRT monitor and the uprise of LCD monitors on the market, experts say that CRT monitors are not dead, but rather they will live as a niche product.

CRT monitors are based of the cathode ray tube technology invented by German physicist Karl Ferdinand Braun in 1897. Cathode ray tubes consist of a glass vacuum tube inside which an electron gun emits electrons that are guided by an electrical field towards the screen. The screen is covered in small phosphorescent elements. The electron beams move back and forth across the back of the screen illuminating the phosphorescent elements. The gun that emits electrons is made up of a cathode and one or more anodes. The cathode, which is a negatively charged metallic electrode, emits electrons that are attracted by the anodes, which are positively charged electrodes. The electrical field which guides electrons is made by the anodes who act as accelerators for the electrons and concentrate them into beams. These beams light the phosphorescent elements on the screen in lines. This is accomplished by using two deflectors (electrified X and Y plates). The magnetic field generated helps the electrodes to move left to right (horizontally) and top to bottom (vertically).

The lit-up dots that appear as a result of the movement of the electrons are called pixels. The number of pixels that a monitor displays is called definition (often confused with resolution) and starts as low as 640x480. Resolution is actually the number of pixels per surface unit which is abbreviated as dpi (Dots per inch). The refresh rate represents how often the image is refreshed each second and it is expressed in Hertz (Hz). Dot pitch is tied up to the image quality. Lower dot pitch means better image quality.

CRT monitors are sold based on the size of their screens, which is measured diagonally, from corner to corner including the case. The measurement is done in inches, CRT monitor size ranging from 15 to 21 inches (38 - 53 cm). The actual size of the screen which is viewable is in fact about 1 inch smaller because of the monitor casing and because the tube can not project the image to the edges of the tube.

While the CRT monitor has some good qualities like high speed response, higher contrast rate than many many LCDs computer monitors, excellent viewing angle, able to display in almost all definitions and refresh rates and has proven to be a reliable display technology the negative aspects of it have proven to be it's undoing  causing its decline and the rise of of LCD monitors despite the fact that these cost more.

Among the negative aspects of the CRT monitors we have the large size and weight, greater power consumption compared to LCD monitors, the fact that lower refresh rates cause noticeable flicker. It's also intolerant of damp conditions, prone to burn-in (older models), internal lethal high voltages, lower maximum brightness than LCD monitors and geometric distortion in the case of non-flat CRTs.

For low budget people and home users it is still a viable alternative since it cost a lot less that a LCD computer monitor.