This document provides an introduction to computers. It describes the basic components of a computer system including the central processing unit, memory, storage, motherboard, and peripheral devices. It also discusses input and output devices, ports, software types, and common uses of computers in daily life such as communication, documentation, and entertainment. The advantages and disadvantages of computer usage are outlined.

1. INTRODUCTION TO
COMPUTER
MPANDA VTC

2. LEARNING OBJECTIVES
• Describe Computer system
• Describe different peripheral devices
• Describe connection ports
• Explain the procedure for connecting peripherals to Micro-computer
system
• Connect peripherals to Micro-computer
• Test the connected Micro-computer

3. What is a computer?
•A computer is an electronic device that
accepts data and instructions from a user,
manipulates the information according to
the instructions, displays the information,
and stores the information for retrieval later.

4. Important terms
• INPUT: This is the command or instruction you enter into a
computer, we call it DATA.
• PROCESSING: The process used by a computer to
change/manipulate input data into information.
• OUTPUT: We call this information, it is what you see (The
processed data).
• STORAGE: Used to describe the way computers store
information

6. Uses of computers in daily lives
• Computer is used for storing information
• COMMUNICATION: Electronic mail (e-mail)
• Social networking (Facebook, Twitter, youtube)
• Creating different types of documents
• RECREATION AND ENTERTAINMENT
• Computers are used in hospitals for medical diagnosis
• Industrial Operations
• Banking
• Shopping

7. Advantages of computer
•FAST: It can do a lot of tasks just within a short
period of time
•MULTI-TASKING: Computer comprises of
multiple functions in work and entertainment
•ACCURATE: Performs a task according to user’s
specifications

8. Disadvantages of computer
• Unemployment
• Wastage of time and energy
• Data Security
• Computer Crimes
• Privacy violation
• Health risks
• Impact on Environment

9. Types of computer
•Desktop
•Laptop
•Tablet
•Server
•Super Computer
•Mainframe Computer

10. Desktop Computer

11. Laptop Computer

12. Tablet Computer

13. Server

14. Super Computer
• A supercomputer is a computer
with a high level of computing
performance compared to a
general-purpose computer.

15. Mainframe Computer

16. Personal computer
•Personal computers (PCs) are computers
typically used by one person in a home or office.
They consist of four fundamental parts namely:-
(a) Monitor
(b) Keyboard
(c) Pointing device
(d) System Unit

17. Monitor
• A monitor is a device used to display the output from a computer.
The main two types of monitor are:-
• Cathode Ray Tube (CRT) Monitor
• Liquid Crystal Display (LCD) Monitor

18. Keyboard
•A keyboard is used mainly for typing
text into your computer. Like the
keyboard on a typewriter, it has
keys for letters and numbers, but it
also has special keys

20. Pointing device
• A pointing device controls the pointer, a small arrow or other symbol
on the display screen.
• The most popular pointing device for a desktop computer is a mouse.
To properly use a mouse:
• Using your right hand, place your thumb on the desk or table top on the left
side of the mouse.
• Your index (pointer) finger should rest on the left button of the mouse.
• Your ring finger and little finger should rest on the right side of the mouse.
• The base of your wrist should rest on the mouse pad or desktop, for stability.

21. Functions of the mouse:
•Pointing
•Selecting
•Scrolling
•Dragging

22. Techniques of using the mouse:
• CLICK: This is when you press a left mouse button at once.
• RIGHT CLICK: This is when you press a right mouse button
once.
• DOUBLE CLICK: This is when you quickly press a left mouse
button twice.
• DRAG: Drag an object on the screen by pressing and holding
down the left mouse button with your index finger while
moving the mouse. When the object is where you want it,
release the button.

23. System Unit
• This is a metal or plastic case used to host the main
computer components. It also consists of a number of
PORTS (normally at the back) and some front through
which different peripherals can be connected.
• PORT: It is a location at the back of SYSTEM UNIT
where a communicating device is going to be
connected to it.

24. Types of ports
• Video Graphics Array (VGA)
port
• Serial port
• Network (Ethernet) port
• Multimedia ports
• Parallel port
• Universal Serial Bus (USB)
Ports
• High Definition Media
Interface Port (HDMI)

25. Peripheral Devices
• PERIPHERAL DEVICE is the term that describes input
and output devices which are connected to the
system unit e.g. mouse, keyboard.
Computer peripheral devices are divided into two main
groups:-
a) Input devices
b) Output device

27. Computer System
• A computer system includes computer hardware and
software.
• Hardware refers to physical components of a
computer.
• Software refers to intangible components of a
computer system, particularly the programs, or list of
instructions, the computer needs to perform a specific
task.

28. Classification of Software

29. Computer inner parts
Motherboard
• The motherboard is the computer main circuit board
• It is a thin plate that holds the CPU (Central
Processing Unit), memory, and expansion cards to
control the video, audio and more
• The motherboard connects directly or indirectly to
every part of the computer.

31. Central Processing Unit (CPU)
• The central processing unit (CPU) is the brain of the computer
• Its job is to carry out all computer commands
• Whenever you press a key, click the mouse, or start an application,
you are sending instructions to the CPU
• The CPU is located inside the computer case (The system unit) and is
found embedded on the motherboard
• The CPU determines how fast a computer can execute instructions
• A CPU speed is measured in megahertz (MHZ), or millions of
instructions per second. Therefore the higher the CPU speed, the
faster the computer can process instructions.

32. Memory and Storage
•Computer memory is the area where
data is stored before or after the
process
• Types of data stored in this area
include programs and data files.

33. Unit of measure for a computer memory and
storage

34. Types of Memory
• Short-term memory: Is a type of memory that is available only for a
short period of time. This memory disappears when the computer is
turned off, so always save your file before turning off the machine.
When you save a file, you are saving it lo long-term memory.

35. Long term memory
• Long-term memory: Is a type of memory that stores
information permanently, even when the computer is
switched off.
• The HARD DISK DRIVE (also called the hard disk) on
your computer is where information is stored
permanently.
• How large the hard disk drive should be depends on
the needs of the user.

36. Removable (External) Storage Devices
•Optical discs (Blu-ray discs, DVDs,
CDs)
•USB flash drives and memory cards
•Floppy disks (diskette)
•External hard disk drives