IntroducingHardware‐Chapter#1
Amy Hissom
Key Terms
1. Advanced Configuration and Power Interface (ACPI) - a power management specification developed by
Intel, Microsoft, and Toshiba. ACPI, which will be part of the next version of Windows, enables the operating
system to control the amount of power given to each device attached to the computer. With ACPI, the operating
system can turn off peripheral devices, such as a CD-ROM players, when they're not in use. As another
example, ACPI will enable manufacturers to produce computers that automatically power up as soon as you
touch the keyboard.
2. Advanced Power Management (APM) - an API developed by Intel and Microsoft that allows developers to
include power management in BIOSes. APM defines a layer between the hardware and the operating system
that effectively shields the programmer from hardware details.
3. Basic input/output system (BIOS) - the built-in software that determines what a computer can do without
accessing programs from a disk. On PCs, the BIOS contains all the code required to control the keyboard,
display screen, disk drives, serial communications, and a number of miscellaneous functions.
4. Binary Number System - Pertaining to a number system that has just two unique digits. For most purposes,
we use the decimal number system, which has ten unique digits, 0 through 9. All other numbers are then formed
by combining these ten digits. Computers are based on the binary numbering system, which consists of just two
unique numbers, 0 and 1. All operations that are possible in the decimal system (addition, subtraction,
multiplication, division) are equally possible in the binary system.
5. Bit – Short for binary digit, the smallest unit of information on a machine. The term was first used in 1946 by
John Tukey, a leading statistician and adviser to five presidents. A single bit can hold only one of two values: 0
or 1. More meaningful information is obtained by combining consecutive bits into larger units. For example, a
byte is composed of 8 consecutive bits.
6. Bus – A collection of wires through which data is transmitted from one part of a computer to another. You
can think of a bus as a highway on which data travels within a computer. When used in reference to personal
computers, the term bus usually refers to internal bus. This is a bus that connects all the internal computer
components to the CPU and main memory. There's also an expansion bus that enables expansion boards to
access the CPU and memory.
7. Byte – Abbreviation for binary term, a unit of storage capable of holding a single character. On almost all
modern computers, a byte is equal to 8 bits. Large amounts of memory are indicated in terms of kilobytes (1,024
bytes), megabytes (1,048,576 bytes), and gigabytes (1,073,741,824 bytes).
8. Cards – Adapter boards or interface cards placed into expansion slots to expand the function of a computer,
allowing it to communicate with external devices such as monitors or speakers.
9. Central processing Unit (CPU) - The CPU is the brains of the computer. Sometimes referred to simply as
the processor or central processor, the CPU is where most calculations take place. In terms of computing power,
the CPU is the most important element of a computer system.
