The monitor is the part of the computer that you receive visual 

information from; it is also called the video terminal, and the video display

unit. There are two types of monitors, LCD (Liquid Crystal Display) and CRT

(Cathode Ray Tube). The LCD monitor is more commonly used because it takes less

energy, it takes up less space, and it has better resolution. the source of a monitors information is ultimately the motherboard. Monitors are

usually at a 3:4 ratio (height: width), and measured in inches diagonally

across the screen. The resolution of a monitor is determined by the number of

pixels the screen has, the more pixels the better. 

Signals from the computer can be sent in digital or analog format. Most CRT monitors require an analog (VGA) connection, which sends a continuous electrical signals and waves, most CRT monitors don't use digital connections, which send pulses of 1's and 0's. Computers work digitally and the computer (or CPU) and convert the information into analog format. The video adapter is a card that converts display information into a signal that is sent to the monitor, it is also called a video or graphics card.The information is sent through the VGA cable which connects to the computer through a D-Sub connector. The VGA connector has fifteen pins in three rows, they send information in a super complicated way that i totally don't understand, but here it is.

1.Red out


2.Green out

3.Blue out



6.Red return (ground)

7.Green return (ground)

8.Blue return (ground)



10.Sync return (ground

11.Monitor ID 0 in

12.Monitor ID 1 in or data from display

13.Horizontal Sync out

14.Vertical Sync

15.Monitor ID 3 in or data clock

The number of colors your monitor can display is determined by the graphics adapter and the monitor capabilities. for example, a display that operates in SuperVGA (SVGA) mode can display up to16,777,216 (usually rounded to 16.8 million) colors.