Download categories of computer hardware

Name: Okoro Kolette Elo-Oghene
Department: Medicine and Surgery
Level: 100L
GST 115 Assignment
CATEGORIES OF COMPUTER HARDWARE
Computer hardware is the physical parts of the computer system. There are the
parts that can be touched, seen and broken. The computer hardware is
categorised into six major components. This includes:
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Central Processing Unit(CPU)
Main Memory
Secondary Storage
Input Devices
Output Devices
Network Hardware
CENTRAL PROCESSING UNIT (CPU)
The CPU is the most essential part of the computer system. It is referred
to as the brain of the computer system. The CPU connects all other
hardware component and takes decision for the computer. All other
computer hardware is attached to the CPU so as to carry out their
function. The CPU does all the reasoning, decision making, and
arithmetic operations.
The CPU is divided into two major parts, namely; The Arithmetic and
Logical Unit (ALU) and The Control Unit (CU).
The Arithmetic and Logical Unit is responsible for the arithmetic
operation and decision makings. Operations like addition, subtraction,
division and multiplication. It also performs logical operations because of
its ability to reason and make decision.
The Control Unit interprets the instruction from the main memory. It
appoints tasks to the ALU and the peripheral devices. It instructs the
ALU and give directives to the other computer hardware. In other words,
the control unit controls all the activities of the computer system.
THE MAIN MEMORY
This is a storage media on the motherboard. It stores data and
instructions to be carried out by the CPU. It is also called the Primary
storage. It is the storage space in computer where data is to be processed
and instructions required for processing are stored. The main memory is
the storage media that the CPU interacts with most times since it closer to
the CPU. The main memory is classified into three types, namely;
 Random Access Memory(RAM)
 Read Only Memory (ROM)
 Complementary Metal-Oxide Semiconductor Memory (CMOS)
RAM is a volatile type of memory. It holds the data and instruction the
computer is working on temporarily. In a situation of power supply, all
data would be lost. When data and information are still stored on the
RAM, it can be edited. The RAM is the storage media that computer
users interact with the most.
ROM is a non-volatile type of memory. Power supply does not affect the
data stored on the ROM. Contents in the ROM can only be read, they
cannot be edited. They are basically used to store instructions of the
activities of the computer system. The Electrical Erasable Programmable
Read Only Memory (EEPROM) allows the instructions stored on it to be
updated or edited but with use of higher than normal electrical voltage.
CMOS is the combination of some of the properties of the ROM and
RAM. It is a hybrid of both memories. It is non-volatile and the content
can be edited and updated. The CMOS cannot store programs. It is used
to store configuration information of the computer system.
SECONDARY STORAGE
The secondary storage is used to store processed data since data is lost on
the RAM after power supply is lost and the ROM is not user friendly. In
this wise, information are stored in the secondary storage. There are three
types of secondary storage, namely;
 Magnetic Media
 Optical Media, and
 Semi-Conducting Media.
Magnetic Media: floppy disk, hard disk and magnetic tapes are basic
types of the magnetic media. The floppy disk portable and has a very
small size of about 1.44MB. It is not durable and slow in operation. They
are old examples of storage media. The hard disk is a huge type of
memory and also determines how powerful a computer system is. It
rotates at a high speed. The magnetic tape is a magnetically coated strip
of plastic on which data are stored. It is very cheap to afford and also
stores large amount of data.
Optical Media: they hold content in digital form that are written and
read by a laser. The optical media is classified into CD and DVD
variations. The Compact Disk (CD) uses laser and technology to store
data of about 640MB. The CD is divided into three. The CD-ROM can
only be read and not over written or edited. The CD-Recordable is
durable if well-kept but data can only be written in it once. The CDRewritable can be rewritten over and over again as the name implies.
The Digital Versatile Disk (DVD) is more advanced than the compact
disk and has higher capacity. The storage space is much more than the
CD. It also has three divisions. The DVD ROM is similar to the CDROM
but of more capacity. It is mostly used by the film making companies.
The DVD-Recordable is also similar to the CD-Rewritable but very much
volume of data. It cannot be overwritten. The DVD-Rewritable can be
overwritten for as many times as possible. They are of various standards.
Magneto-Optical Disk (MOD) combines both the magnetic and optical
methods to store data. It is more reliable than the DVD and has similar
storage amount as the DVD. It can also be rewritten as many times as
possible.
Semi-Conducting Media: they are often referred to as “Flash
memories”. They make use of semi-conductor clips to store data. They
are mostly found in portable devises such as digital cameras, mobile
phones, MP3. They are very reliable and durable. Examples include;
Secure Digital Card (SD card), smart media card (SM card).
INPUT DEVICES
These are the devises that enables the computer user to enter data and
commands into the computer system. They are peripheral computer
hardware equipment used to provide data and control signals to an
information processing system such as computer or information
appliance. It can be said to be any machine that feeds data into the
computer. It allows the user to interact with the computer and control the
computer. Example of the input devices includes;
Mouse, keyboard, joystick, trackball, image scanner, digital camera, Optical
Mark Recognition (OMR) reader, microphone, Automated Teller Machine
(ATM), light pen, barcode reader, biometrics scanner and so on.
OUTPUT DEVICES
These are devices that present digital information in the form that human can
understand. It is any piece of computer hardware equipment used to
communicate the results of data processing carried out by an information
processing system (computer) which converts the electronically generated
information into human readable form. An output device could be referred to as
any peripheral device that receives data from the computer, usually for display,
projection or physical reproduction. It converts a computer’s output to a form
that can be seen, heard or used as an input for another device, process or system.
Examples includes; printers, monitors, speakers, projectors, headphones, robots,
fax machines, cathode ray tubes and many more.
CONNECTIVITY HARDWARE
These are the peripherals that connect a computer to different kind of networks.
It enables the computer to be physically connected to the network. There are
various types of connectivity hardware, the ones that are used to replicate
network signal, enables computer to connect and transmit data over phones and
many more. Some of them are explained below;
Repeaters: this is a network device that is used to replicate a signal as it
weakens when travelling across a network.
Router: this is an intelligent device used to connect two or more individual
networks. When it receives a signal, it looks up the address and passes it to the
appropriate network.
Bridges: this is used to connect to different Local Area Networks or two
segments of the same LAN by forwarding traffic between segments.
Hubs: this is a central point of connection between media segment enabling
network extension to accommodate more personal computers.
Other examples include; Modem, brouters, gateways, multiplexer, channel
service unit and many more.