Microsoft Office Tutorials and References
In Depth Information
represents a letter or character on the keyboard; for example, the ASCII code 65 represents
the character A , and the ASCII code 97 represents a . Computers translate ASCII code into
binary data so that they can process it. Figure 13 shows sample ASCII code.
Sample ASCII code representing letters and symbols
As a computer user, you don’t have to know the binary representations of numbers,
characters, and instructions, because the computer handles all the necessary conversions
internally. However, because the amount of memory in a computer and its storage capacity
are expressed in bytes, you should be aware of how data is represented. Storage , or memory
capacity , is the amount of data, or number of characters, that the device can handle at any
given time. A kilobyte (KB or simply K) is 1,024 bytes, or approximately one thousand bytes.
A megabyte (MB) is 1,048,576 bytes, or about one million bytes. A gigabyte (GB) is
1,073,741,824 bytes, or about one billion bytes. You will see the symbols KB, MB, and GB
refer to both processing and storage capacity.
The two most important components of personal computer hardware are the microprocessor ,
a silicon chip designed to manipulate data, and the memory , which stores instructions
and data. The type of microprocessor and the memory capacity are two factors that
directly affect the price and performance of a computer.
The microprocessor, such as the one shown in Figure 14, is an integrated circuit (an
electronic component called a chip ) which is located on the motherboard inside the com-
puter. The terms processor and central processing unit (CPU) also refer to this device,
which is responsible for executing instructions to process data.
An Intel Pentium 4 microprocessor