A monitor or display (sometimes called a visual display unit) is an electronic visual display for computers. The monitor comprises the display device, circuitry, and an enclosure. The display device in modern monitors is typically a thin film transistor liquid crystal display (TFT-LCD), while older monitors use a cathode ray tube.
CRT Means “Cathode Ray Tube”, CRT monitor has more lines of dots per inch, higher the lines more amount of the resolution. It creates the picture by number of rows or lines of the small tiny dots. Consider this Resolution 1024 x 768 resolution will be sharper than 800 x 600 resolution. It describes the technology inside an analog computer monitor.