Numbers within the computer are represented in binary form. In fact, all information is somehow represented using binary values. The reason is that each storage location within a computer contains either a low-voltage signal or a high-voltage signal. Because each location can have only one of two states, it is logical to equate those states to 0 and 1.
In fact, you can forget about voltages and think of each storage location as containing either a 0 or a 1. Note that a storage location cannot be empty: It must contain either a 0 or a 1.
Recall that each storage unit is called a binary digit, or bit for short. Bits are grouped together into bytes (8 bits), and bytes are grouped together into units called words.
The number of bits in a word is known as the word length of the computer. For example, IBM 370 architecture in the late 1970s had
Modern computers are often 32-bit machines (such as Intel's Pentium IV processor) or 64-bit machines (such as Hewlett-Packard's Alpha processors and Intel's Itanium 2 processor).
However, some microprocessors that are used in applications such as pagers are 8-bit machines. The computing machine you are using, whatever it is, is ultimately supported by the binary number system.