Computer Basics - Computing Fundamentals - page 15

Table.1 1 Common Quantities of Bytes
Term Number of Bytes

Kilobyte (KB) 1024 (approximately one thousand)

Megabyte (MB) 1,048,576 (approximately one million)

Gigabyte (GB) 1,073,741,824 (approximately one billion)

Terabyte (TB) 1,099,411,627,776 (approximately one trillion)

Petabyte (PB) 1,125,899,906,842,624 (approximately one quadrillion)

Both memory and storage capacities are measured in bytes. For example, a computer might have 8GB RAM
(memory) and a 500GB hard drive.

NOTE

Input Devices
An input device provides a way to get data into the computer. The oldest
and most common input device is a keyboard . A desktop PC has an exter-
nal keyboard, while a notebook PC has a built-in keyboard. Tablets and
smartphones have a software-based keyboard that pops up onscreen when
needed.

keyboard An input device that allows users to
type data into a computer using a standard set of
typing keys.

Computers that use a graphical interface usually employ a pointing
device. The pointing device moves an onscreen pointer (usually an
arrow) to align with objects onscreen, and then the user presses a but-
ton on the pointing device to do something to the pointed-at object. A
mouse is the most common pointing device, but there are many other
types too, such as trackballs, touchpads, and touch-sensitive screens. You
will learn more about input devices in Chapter 3, “Input, Output, and
Storage.”

Processing Devices
The motherboard is the large circuit board inside the computer that
everything else plugs into. The key components located on the moth-
erboard are the processor (also called the Central Processing Unit, or
CPU) and the memory (also called Random Access Memory, or RAM).
To support these components, the motherboard has electrically conduc-
tive pathways called buses that carry the data from place to place, and
a chipset , which is a controller that directs the bus traffic. Figure 1.13
shows a motherboard removed from the computer case so you can see it
more clearly.

motherboard A large circuit board inside a
computer that controls the operations of all other
components.

processor The chip in the computer that
performs math calculations, processing data. Also
called the Central Processing Unit (CPU).
memory Temporary electronic storage that holds
the values of data bits using transistors.

bus A conductive pathway built into a circuit
board, used to move data.
chipset The controller chip on a circuit board.

Chapter 2 covers these components in more detail and explains how they
work together.