Page 28 - Computer
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Computer Science Note: In Figure 2.1, lines indicate (iv) Storage Devices: These devices,
such as hard disk drives (HDDs)
those components found inside a
or solid-state drives (SSDs), are
computer case.
used for long-term storage of
data and programs.
Computer case or system unit
FOR ONLINE READING ONLY
A computer system unit, sometimes
PSU provides electrical power
called a system unit or computer case, (v) Power Supply Unit (PSU): The
is the enclosure that houses the main to the computer system and its
internal components of a computer. Its components.
primary role is to protect and arrange (vi) Expansion Slots: These slots
these internal components and connect enable the addition of extra
them to external components which are components, like graphics cards,
usually known as peripherals. sound cards, or network cards.
(vii) Cooling System: The system
(a) Internal components unit often includes fans or other
(i) Motherboard: This serves cooling mechanisms to prevent
as the primary circuit board overheating of the components.
that establishes connections (viii) Ports and Connectors: These are
and enables communication used to connect external devices,
among all the other computer such as monitors, keyboards,
components. mice, and USB devices, to the
(ii) Central Processing Unit (CPU): computer.
Sometimes called the “brain” or
CPU, this component handles (b) External components
most computations and carries External components or parts of a
out instructions within the computer system unit are typically
computer. those elements that are not housed
(iii) Memory: This includes Random within the computer case (tower). These
components are often peripherals or
Access Memory (RAM) and accessories that connect to the computer
Read-Only Memory (ROM). to enhance its functionality or provide
RAM is used for temporary interaction with the user. The details of
storage of data and instructions computer hardware will be covered in
that the CPU needs to access Chapter Three.
quickly, while ROM contains
permanent instructions that Software: These are instructions that
cannot be modified. govern the operation of a computer
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