Quadrants:
Fig. 4
To understand this system we need to learn how to divide a ball into four
quadrants (areas) as shown in Figure above.
We can divide a pool ball (including cue ball) virtually into 4 equal quadrants. The small circle in the center is the center of the pool ball. Other 4 quadrants will be numbered from 1 to 4 virtually. Though numbering is not important, but it helps in starting to learn the system. After numbering, we will be able to recognize a shot easily, such as, 1 to 1 shot, 1 to center shot, and 1 to 4 shot. Figure 5 shows the four quadrants with numbers.
Fig. 5