ABSTRACT
Newspapers and magazines that list television programs often use a grid to represent an
evening’s schedule. In many of them, the channels run vertically down the left side of the
grid, while half-hour time “slots” run horizontally along the top. (Fig. 1.1 shows one such
grid for a summer day in the 1990s.) The reasoning behind this array is obvious. At a glance, we
can fix our location in the grid, noting the axis of channel (say, channel 9) and the axis of time
(say, 7:00). After figuring that location, we can quickly see what will follow the current program
in time (horizontal) and what is happening on other channels at that same time (vertical).
