What is a computer
• An electronic device that works with 4
functions namely: input, process, output and
storage.
• Input: accepts data (similarly known as raw facts).
• Process: analysis or we can simply say does
the thinking.
• Output: produce results or outcome
(referred to as information).
• Storage: stores the information for later usage.
Computer Cycle
Processing
Input:
Accepts
data
Computer
Cycle
Storage
Output:
Produces
results
• Data: is a collection of raw unprocessed facts,
figures and symbols.
• Processing: to process data into information a
computer uses hardware and software.
• Information: is data organized to be meaningful
and useful.
• Storage: is a core function and component of a
computer. The CPU is what processes data into
information. The CPU is found in the computer
storage which is what makes storage the
fundamental component of computers.
Components of a computer
• A computer is made up of 4 main components:
• Input Devices – keyboards, mouse &
microphone.
• Output Devices – monitor, speakers and
printers.
• Secondary Storage Devices – HDD, DVD and
CD.
• Processor and Primary Storage Devices – CPU
and RAM while ROM is secondary storage.
Information and Computer
Literacy
• Computer literacy refers to the knowledge and
understanding of computers and their uses.
• Information literacy refers to the ability to
identify what information is needed, understand
how information is organized mostly be able to
use and share information.
Advantages of using a computer
• Speed – computer may perform millions of operations
in a second.
• Reliability – they are dependable and reliable since
they hardly break.
• Consistency – given the input the computer will
produce the same output. GIGO
• Storage – computers store large amount of data which
available for processing anytime when needed.
• Communication – computers allow users to
communicate with one another. Remember a
cellphone is an example of a computer.
Disadvantages of using a computer
• Violation of Privacy – when confidential information is not
properly protected.
• Public safety – computers are not only used by adults
therefore children need to be protected from some
information or content.
• Impact on Labor Force – computers may tend to replace
millions of employees therefore it is crucial to keep their
education up to date.
• Health Risks – individuals need to be not obsessed with
using computers as they may lead to health injuries.
• Impact on Environment– The manufacturing of computers
is polluting the environment and depleting natural
resources.
Categories of Computers
Personal Computer is a computer that can
perform all its input, processing, output and
storage and storage activities by itself and is
intended to be used by one person.
Types of Personal Computers
• Laptops.
• Tablets.
• Desktop.
Server Computer
• A server is a computer that provides one or
more services to other computers or devices
called clients. Servers can provide various
functionalities often called services such as
sharing data, storing content etc. A network
is a collection of computers and devices
connected together often wirelessly.
Categories of Mobile Computers
Mobile device is a small computing device ,
typically small enough to be handheld having a
display screen with a miniature keyboard along with
other icons and buttons that can be pressed.
Types of Mobile Computers
• Smart Phones.
• Digital Cameras.
• Portable Media Players.
• E-book Readers.
• Game Devices.
INPUT
• An input device is any hardware component that
allows users to enter data and instructions into a
computer or mobile device.
Types of input devices:
• Keyboards.
• Pointing methods.
• Voice and video input.
• Scanners.
OUTPUT
• An output device is any hardware component
that allows users to view or receive data and
instructions from a computer or mobile device.
Types of output devices:
• Printers.
• Displays.
• Speakers.
• Monitor.
INTERNET
Internet is a worldwide collection of computer
networks that connects millions of users.
A network is a collection of computers and
devices connected together, often wirelessly via
communication devices and transmission media.
Networks allow computers to share resources
such as hardware, software, data, and
information. Advantages of sharing resources
saves time and money.
Types of Communication Networks -we are just
going to look at the 3 main types of networks.
Local Area Network (LAN) – data network that
interconnects computers within a limited area
such as schools, campus or an office building.
Metropolitan Area Network (MAN) – data
network that interconnects users with computer
resources in a geographic region.
Wide Area Network (WAN) – data networks
usually used for connecting computers that spans a
wide geographical area. WANs are used to connect
cities, states and countries.
Digital Security and Safety
• Many people rely on computers to create, store,
manage and protect information but there are
other issues that may harm that information.
These factors include viruses and other malware,
privacy, health concerns and environmental
issues. (discussed on the 7th slide)
• Malware is a software that acts without a user’s
knowledge and deliberately harm the computer
operations.
Programs and Applications
• Software is also called program which consists of
series or instructions that tells a computer what
to do or perform a certain task. Software is often
divided into 2 categories :
• System Software – includes the OS and all the
utilities called tools that enable a computer to
function.
• Application Software – includes programs
that do the real work for users.
Understanding the Application better
Computer Hardware
Physical components of a computer
System Software
File Management Tools
Operating Systems
Application Software
Word Processing, Spreadsheets
Database & Games