Data items processed by computers form a data hierarchy that becomes larger and more complex in structure as we progress from the simplest data items (called “bits”) to richer data items, such as characters, fields, and so on. Figure 1.1 illustrates a portion of the data hierarchy.
The smallest data item in a computer can assume the value
0 or the value
1. Such a data item is called a bit (short for “binary digit”—a digit that can assume either of two values). It’s remarkable that the impressive functions performed by computers involve only the simplest manipulations of
1s—examining a ...