The document discusses the basic concepts of computers including their components, functions, and classifications. It describes how computers accept input, process data using a CPU, and provide output. Computers have both main memory for fast processing and secondary memory for storage. They are classified based on their size and processing power, ranging from microcomputers for individual use to minicomputers, mainframes, and supercomputers that can support multiple users and huge data processing tasks.

1. Chapter 1 : Computer Concepts
IT 12 | Fundamentals of Ms. Jennifer O. Calleja |
Programming and Database IT Instructor
Theory and Applications

2. Ms. Jennifer O. Calleja |
IT Instructor
Objectives
• At the end of this module you should be able to:
 Explain how computer works
 State the functions of each basic hardware
component of a computer system
 Classify computers

3. Ms. Jennifer O. Calleja |
IT Instructor
Computer
is an electronic device that accepts data, stores
and processes the data and generates
information as output.

4. Ms. Jennifer O. Calleja |
IT Instructor
input Computer (stores output
Data info
and process data)
A computer

5. Ms. Jennifer O. Calleja |
IT Instructor
Data and Information
Data is a raw,
unprocessed data
Information is a
processed data

6. Ms. Jennifer O. Calleja |
IT Instructor
Four Basic Functions:
• Input – the procedure of feeding data into a
computer
• Process – refers to the operation of
manipulating and transforming data into
something useful.
 Program – a set of written instructions, is what tells the
computer how to manipulate and transform the data it
was given into information
• Output – the result of the processing function.
• Storage – computers can save data so that ir can
be used at another time.

7. Ms. Jennifer O. Calleja |
IT Instructor
SAQ 1-1
• How does the computer process data?

8. Ms. Jennifer O. Calleja |
IT Instructor
ASAQ 1-1
• The computer processes data by following a
set of instructions called a program

9. Ms. Jennifer O. Calleja |
IT Instructor
Computer Systems Components
• Hardware – refers to the tangible components of
a computer system
• Software – refers to the set of instructions
written in a code.

10. Ms. Jennifer O. Calleja |
IT Instructor
Basic Hardware Components
• Input devices – perform the two most basic
computing tasks : issuing commands and
entering data.
 Data entry – defined as the process of entering data
into the computer memory and issuing commands
that tell the processor how to work with the data.

11. Ms. Jennifer O. Calleja |
IT Instructor
Examples of Input device:
• Keyboard
• Mouse
• Trackball
• Joystick
• Lightpen
• Video input device
• Scanners

12. Ms. Jennifer O. Calleja |
IT Instructor
Basic Hardware Components
• Output Device
after processing data fed into the computer with
the use of input devices, the information must
now be outputted in a form understood by human
beings. For this purpose, computer system
components collectively called as output devices
are used.

13. Ms. Jennifer O. Calleja |
IT Instructor
Examples of Output device:
• Printer
• Video monitors
• Speakers
• modem

14. Ms. Jennifer O. Calleja |
IT Instructor
Basic Hardware Components
• Central Processing Unit (CPU)
CPU does the data processing. Its job is to fetch
instructions (programs) from the main memory,
decode, and execute it.

15. Ms. Jennifer O. Calleja |
IT Instructor
Parts of a CPU:
• Control Unit (CU)
▫ can be described as a sort of circuitry that
supervises and controls the path of information
that runs over the processor and organizes the
various activities of those units that lie inside it.
• Arithmetic Logic Unit (ALU)
▫ Involves comparing two items and determining
whether one is greater than, equal or less than the
other.

16. Ms. Jennifer O. Calleja |
IT Instructor
Companies that design and
Manufacture CPUs:
• Intel
• Motorola
• DEC
• SUN
• IBM
• AMD

17. Ms. Jennifer O. Calleja |
IT Instructor
SAQ 1-2
• What specific components of the
computer does the arithmetic
computations?

18. Ms. Jennifer O. Calleja |
IT Instructor
ASAQ 1-2
• The arithmetic/logic unit (ALU)

19. Ms. Jennifer O. Calleja |
IT Instructor
Basic Hardware Components
• Main Memory and Secondary Memory
when the CPU processes the data, it uses the
memory as temporary storage to aid in the
calculations.

20. Ms. Jennifer O. Calleja |
IT Instructor
Bits and bytes
• The data and programs are stored in the
memory in the form of binary digits (0 and 1).
Numbers are all represented using the binary
system, and text and characters are coded in
binary.
▫ 8 bits = 1 byte
▫ 1024 bytes = 1 kilobyte
▫ 1024 kilobytes = 1 megabytes
▫ 1024 megabytes = 1 gigabyte

21. Ms. Jennifer O. Calleja |
IT Instructor
Computer Memory
• Consists of the main memory and the secondary
memory. The difference between the two types
of memory lies in the technology used.
• Main Memory – stores data using electric
current flowing around the loop of wire.
• Secondary Memory – usually uses magnetic
materials, just like those found in cassette tapes.

22. Ms. Jennifer O. Calleja |
IT Instructor
Comparison of Computer Memory
Memory Technology Limitations, Advantages and
Type Disadvantages
Main Memory Uses electric current -Very expensive
-Fast access
-Volatile
Secondary Uses magnetic -Relatively cheap
Memory materials -Slow access
-Non-volatile

23. Ms. Jennifer O. Calleja |
IT Instructor
SAQ 1-3
• Why do computers need to use both
types of memories (main and
secondary)?

24. Ms. Jennifer O. Calleja |
IT Instructor
ASAQ 1-3
• It uses main memory to be able to
process data at high speeds (remember
how the memory is used as temporary
storage?) and it uses secondary memory
to preserve data.

25. Ms. Jennifer O. Calleja |
IT Instructor
COMPUTER SOFTWARE
• It can be categorized into two classes :
▫ Applications Software
▫ System Software

26. Ms. Jennifer O. Calleja |
IT Instructor
Application Software
• Are programs that are used by people to solve
their individual needs.
▫ Examples:
 Word Processor
 Spreadsheet programs

27. Ms. Jennifer O. Calleja |
IT Instructor
Systems Software
• Are programs that control the operations of the
computer hardware.
▫ Task of Systems Software
 Starting up of the computer
 Loading
 Executing applications software.

28. Ms. Jennifer O. Calleja |
IT Instructor
CLASSIFICATION OF COMPUTERS
• Computers are usually classified according to
their sizes and processing speeds. But since
technology changes very rapidly, no absolute
measures to classify computers exist.

29. Ms. Jennifer O. Calleja |
IT Instructor
Classification of Computers
• Microcomputers
▫ refer to small desktop systems
made popular by IBM in the
early 80s. They are also called
personal computers and are
usually used for individual
tasks such as word processing,
spreadsheet computations and
other interactive applications.

30. Ms. Jennifer O. Calleja |
IT Instructor
Classification of Computers
• Minicomputers
▫ are more powerful than
microcomputer and are
intended to support several
users who are concurrently
doing different tasks. They are
widely used in real time
applications such as air traffic
control.

31. Ms. Jennifer O. Calleja |
IT Instructor
Classification of Computers
• Mainframes
▫ are large systems that can
process huge amounts of data at
a very high rate. The main
difference between mainframes
and minicomputers is their
input/output capacity and the
applications for which it is used.

32. Ms. Jennifer O. Calleja |
IT Instructor
Classification of Computers
• Supercomputers
▫ are the fastest computers and
achieve processing speeds
more than 10 times that of the
minicomputers. To achieve
high speeds, they usually
consists of several processors
running simultaneously.

33. Ms. Jennifer O. Calleja |
IT Instructor
SAQ 1-4
• Differentiate microcomputer and
minicomputers.

34. Ms. Jennifer O. Calleja |
IT Instructor
ASAQ 1-4
• Microcomputers are less powerful than
minicomputers. They are designed for
individual use, while minicomputers are
designed to handle several users at a
time.

35. Ms. Jennifer O. Calleja |
IT Instructor