Some applications give you a choice of how you want information sent to the display. The choice is 40 columns or 80 columns. To understand what that means, imagine that the screen is a grid 40 squares across by 24 squares down. Each square on the grid can hold one character. (See Figure 2-2.) In 80-column format, the grid is 80 squares across by 24 squares down. With the 80-column display, you can fit twice as many characters per line as with the 40-column display, but the characters are half as wide. Some display devices, like TV sets, can display text only in the 40-column formatthey don't have sharp enough resolution to display the narrower 80-column characters clearly.
Chapter 2: Once Over Lightly