2. Computer Fundamentals
Computers are everywhere! Anywhere you
look and anywhere you go, there are computers.
There are computers, or some kinds of it, at
home, in school, and at the office. Today, most
appliances and gadgets are computerized, which
means that a program or software runs our cell
phones, LCD TVs, cars, and even our watches.
The computer has made a big difference in
our lives these days. Let us get to know it better.
3. Defining the term computer
We already have an idea of what a
computer is. However, let us study the
definitions of a computer to better understand
the concept.
4. A leading dictionary defines a computer as
a “programmable and usually electronic device
that can store, retrieve, and process data.”
On the other hand, a computer is also
defined as “a general-purpose machine that
processes data according to a set of instructions
that are stored internally either temporarily or
permanently.”
5. We can conclude from the definitions that a
computer manipulates data or bits of information in
some way according to some “orders” or
instructions and comes up with some meaningful
result or output.
The devices and machines that we see in our
offices, schools, and homes are computers because
they can process data or information and give us
useful outcomes. A teacher uses a database
program in a computer, for example, to come up
with the average grades of his students: while a
businessman uses a similar machine to know his
projected earnings for the coming year.
6. Computers have developed so fast because
of their usefulness. They now appear in various
sizes, shapes, functions, and power, and are
used for a variety of purposes and needs.
7. Computers According to size and
power
Computers are classified in various ways.
First, they differ according to size and power.
Computers can be supercomputers, mainframes,
minicomputers, and microcomputers.
8. Supercomputers
Supercomputers are the largest and most
powerful computers. They are also the most
expensive because they are custom-made for the
needs of governments and international groups and
companies.
Supercomputers are used for every special
purposes, like in scientific and engineering
applications, including analyzing data from space
probes, researching nuclear energy, creating
weather maps, and finding oil.
9. Some examples of supercomputers are
GRAPE, also known as Gravity Pipe, which is
used for gravitational computations; Anton,
used for studying molecular dynamics; and Cray
XT5, considered as one of the world’s most
powerful supercomputers, used for various
applications that need great ability to process
information.
10. Consider this: supercomputers are so
powerful that they can analyze weather patterns
and come up with a weather map in minutes;
whereas an ordinary computer can probably
come up with the same calculation in weeks or
longer.
11. Mainframe Computers and
Minicomputers
The second group of computers in terms of
computing power is the mainframe. A
mainframe computer is a large computer that
can process data at a very high rate of speed. It
is mainly used by big businesses and companies
to process and compute large, bulk amounts of
data and handle millions of transactions.
12. Mainframes are typically used for very
large data processing such as those of bank
transactions, census and consumer statistics,
airline ticketing and large management and
payroll needs.
You may never see a mainframe computer
because it is housed in a large building
somewhere. For example, when you withdraw
money from your bank account, the bank most
often uses a mainframe computer to accomplish
the transaction.
13. A mainframe operates not as a single
computer, but as a number of virtual machines
for it has 16 or more CPUs or “brains” to use for
its processing. Thus, it can effectively replace
hundreds of stand alone computers, providing
more efficiency at the same time.
A minicomputer, on the other hand, is
another type of multi-use machine that is
smaller, less expensive, and less powerful than
mainframe. This is used in mid-range businesses
and companies for their processing needs. This
can also support simultaneous applications.
14. Unlike mainframes, which are still widely
used for their processing power, minicomputers
are practically out of use today, except in a few
installations and companies. They have been
replaced by network servers, which can also do
multi-user and related applications.
15. Microcomputers
Probably the most popular kind of computers are
the microcomputers. They first appeared in the late
1970s and has then developed into very fast and
powerful machines. Microcomputers can be workstations
and personal computers (PCs).
Workstations are powerful machines usually used
by an individual user at a time. Their tremendous
computing speed makes them a favorite of scientists,
engineers, and multimedia artists. They handle complex
data like 3D designs, animation, and image rendering,
and usually run one particular program such as graphics
applications.
16. The machines used by most people are the
personal computers (PCs). The term “personal
computer” first appeared in 1981 when
International Business Machines (IBM) launched its
IBM Personal Computer model. Since then,
computers that are for individual use are called
personal computer. The PC has become the most
used computer in the world.
PCs, especially the recent models, have plenty
of computing power for the user. These machines,
which are used in most organizations and homes,
have a variety of uses too, be it accounting, word
processing, graphics design, database management,
and other common application.
17. PCs are either desktop computers or portable
computers. Desktops are the ones with a monitor
and a Central Processing Unit (CPU) usually placed
on a computer table or desk, hence the name. You
can find desktops in most businesses and
companies. Previously, all PCs are desktops, but
now there portable types.
The portable PCs are the laptop computer, a
light and small computer that one can carry to
school or work. You can rest it on your lap while
using, hence the name. The laptop’s size and weight
does not reveal its computing power, but some
models are even more powerful and have faster
speed than most desktops.
18.
19. Other portable computers include the
notebook computer, which weighs less than a
laptop but is as powerful and can be put inside a
briefcase like a notebook, hence the name; the
personal digital assistants (PDAs), which are
handheld devices serving as electronic organizers
that enable users to communicate and use simple
programs like word processing and task scheduling;
and other devices like gaming consoles, mobile
phones, and computers in various gadgets and
appliances. Because they are portable, these
machines generally cost more than desktop
computers.
20. REVIEW QUESTIONS
1. Give a working definition for the key terms
given in Key Terms and Concepts.
2. What are the similarities and differences
between a supercomputer and a mainframe
computer?
3. What is a notebook? Describe its
characteristics.
21. What the computer can and cannot
do
1. They can do repetitive work – you can feed
data which will be repeatedly process or
analyze for days or even months, to a
computer and the computer, unlike a human,
will not grow tired
2. They can operate at a very high speed – A
normal computation, which can take weeks
or months for a human, may just take the
computer hours or even seconds to make.
22. 3. They can compute with the highest degree of
accuracy – Computers will never make mistakes
in the results of a computation, unless there is
something wrong with the data or information
given to them.
4. They do logical processing strictly – People
can also think logically, but there are times when
they let emotions control their decisions.
Computers will always follow the instructions
given to them, and will never run different from
their programming.
23. People now utilize computers for various
purposes.
Computers are now utilized by people for
work (word processing, spreadsheets,
presentation software); for play (games,
listening to music, watching movies); for getting
online (browsing, researching, downloading);
and for keeping in touch (emailing, chatting,
video conferencing).
24. Even with these given capabilities,
however and even in this day and age,
computers are still limited in many ways on
what they can do. For example, while computers
can be good in providing editing advice or
vocabulary and grammar tips, they cannot by
themselves write prose or content that is good
enough for comparable to that written by a
human writer.
25. The Computer Process
Another way of looking at computers is
knowing what they can do. They can
1. Receive input
2. Process information
3. Produce output
4. Store information
these four basic functions are all there is to a
computer, and their convergence is known as the
computer process
27. Input – is something that enters the computer
process. It can be data fed into a computer, a
keyboard stroke, a click of the mouse, or
information from other output devices. It may
also come from files or data from storage. Input
naturally flows or continues into the stage called
process.
Process – is the stage where data and
information, as well as other inputs are
processed in various ways: converted,
combined, analyzed, computed, operated on,
or changed.
28. Output – is the level where the result of the
processing of data is shown. It can be the video
display of a monitor or screen. It can be the hard
copy from a printer. In some cases, the output or
result is not shown immediately, but is kept in
storage for future reference or retrieval.
Storage – is the function of keeping and storing
processed data or information. The stored data can
be referenced or retrieved in the future.
Sometimes, data is retrieved for input purposes,
such as the BIOS data that is referenced and read
when you open your computer.
29. 1. They can compute with the highest degree
of accuracy. Computers will never make
mistakes in the results of a computation,
unless there is something wrong with the
data or information given to them.
2. They can operate at a very high speed A
normal computation, which can take weeks
or months for a human, may just take the
computer hours or even seconds to make.
30. 3. They do logical processing strictly. People can
also think logically, but there are times when
they let emotions control their decisions.
Computers will always follow the instructions
given to them, and will never run different from
their programming.
4. They can do repetitive work you can feed
data which will be repeatedly process or analyze
for days or even months, to a computer and the
computer, unlike a human, will not grow tired
5.
31. Components of the Computer System
Aside from the different functions in the
computer process, another way to understand
the workings of the computer is to know the
various components of the computer system
and how their confluence or combination results
to the overall workings of a computer or
machine.
32. Hardware – is the component of the computer
system that one can touch and see. It includes
the different input, processing, output, and
storage devices, such as , the keyboard, the
monitor, the mouse, CPU housing, the
integrated circuits, the microprocessor, the hard
disk, the power cable, and even the power
supply physically, among others.
33. Software - on the other hand, is the sets of
instructions or programs that run the hardware
itself. It includes the operating system that runs
the overall functioning of the machine, as well
as the different programs that allow one to
create letters, connect to the Internet, or
compute for numbers, among other things.
Software cannot be seen or touched, but its
effects can be observed.
34. Peopleware – for its part, is the people who use
and manage computers. Included here are the
ordinary computer users who utilize the
computer for their daily needs, as well as a host
of computer engineers and scientists, systems
designers, information technologists,
programmers, and the like. Peopleware create
hardware and software.
35. How Computers Think
The functions of the computer process and the components of
the computer system give a good idea of the workings of computer
devices, but these do not yet reveal how computers think.
Although there are times when computers appear to think and
process information like human beings, the fact is that computers
think or handle information in an entirely different manner.
Computers do not understand information as it appears to us
people. Information, which is something that can be communicated,
may appear as words, numbers, text, photos, videos, and so on, but
the computer does not comprehend them as such. For example, the
letter A is not understood by the computer as letter A, but as a
combination of ON and OFF impulses.
36. Let us illustrate this impulse as a light bulb
and in turn refer to the light bulb as a bit. By
itself, a light bulb can either be ON or OFF, which
translates to just two possibilities. Just like an
ON/OFF switch, it is easy for a computer to
know whether a bit is ON or OFF.
128 64 32 16 8 4 2 1
192.168.1.0
(11000000.10101000.00000001.00000000)
37. Different Uses and Applications of Computers
Aside from knowing the functions of the
computer process, the components of the
computer system, as well as how computers
think, it is also important to get an overview of
the different uses and applications of
computers. In today’s technology-driven era,
computers have almost innumerable
capabilities, but the most important uses are as
follows:
38. 1. Word Processing and Desktop Publishing
2. Spreadsheets and Statistical Software
3. Database Software
4. Educational Software
5. Graphics and Games
6. Multimedia
7. Telecommunications and Networking
8. Artificial Intelligence
9. Robotics
39. 1. Word Processing and Desktop Publishing
These two are probably the most popular
and widely used among the applications. Word
processing pertains to communication through
words and text, such as the writing of a letter,
memo, or correspondence. Desktop publishing
is the development and conversion of an idea
into a publication, such as a brochure, manual,
or book. Students, writers, and publishers are
the usual users of word processing and desktop
publishing programs.
40. 2. Spreadsheets and Statistical Software
With these software, computers can be
used to calculate and process numbers. Using
spreadsheets, numbers and values can be
placed in rows and columns to come up with
specific computations on them. Spreadsheets
are invaluable in computing grades, payroll, and
sales figures, among others.
41. 3. Database Software
Because of their fast and powerful
computing ability, computers can easily
manipulate, store, classify, and change data and
information. With the use of database software,
information can be converted and stored into
electronic form for easier retrieval and
manipulation. Health records, for example, can
be transformed into electronic files for faster
retrieval of health information which may be
crucial for a patient’s survival.
42. 4. Educational Software
Electronic books, booklets, and
encyclopedias now abound, providing students
with almost limitless references for their needs.
Students only need to know the information or
reference that they need.
43. 5. Graphics and Games
Computers are also immensely capable of
utilizing and producing different kinds and forms
of graphics, from simple designs to more
intricate ones, charts and graphs, as well as 3D
animations.
44. 6. Multimedia
Audio and video in various features and
format can be delivered by computers, resulting
to a wonderful multimedia experience. Even
simple users can create their own home video
using simple video editing tools.
45. 7. Telecommunications and Networking
More instances of human communication
are done nowadays using the computer. With
the Internet, users can email, chat, call, and hold
a video conference with another user or even
with many users anytime and anywhere in the
world.
46. 8. Artificial Intelligence
Computers are also now being used by
experts to develop programs and designs that
approximate human intelligence, which is known as
the field of artificial intelligence.
9. Robotics
One very interesting use of computers is
programming robots or machines that imitate
human movement or action. This field, known as
robotics, is a growing technology used today in
various applications.
47. The Windows Desktop
When Windows begins, the very first thing the user see is the
desktop. It is where you, the user, will start. The desktop is the whole
graphics array that one sees which includes a host of commands, icons,
menus, and other objects that one will work on.
As you can see, the Windows desktop has several important
elements, as follows:
1. Start button – Located on the lower left part of the screen, this
button, which has the Windows logo on it, gets the user to start
his computing work.
2. Taskbar – This is the long bar on the lower part of the screen that
may contain programs and documents that the user normally
runs, as well as minimized programs that one is working on
48. Knowing Hardware
Input Devices
Input devices are devices that accept input
from the user in whatever form. They are the
most touched of all devices, as users regularly
use, hold, touch, or press them to instruct the
computer and operate it.
The two most used input devices, without
which a computer user cannot really use the
machine, are the keyboard and the mouse.
49. The Ever Useful Keyboard
Built based on the standard typewriter
keyboard, the computer keyboard has been a
constant companion of the computer, especially
since the advent of PC in the 1980s. The keyboard
provides standard alphanumeric keys similar to a
typewriter, but has also other keys and functions for
various purposes.
The following is a layout of a regular keyboard
usually used for PCs. Keyboards for Macintosh and
Apple computers have a somewhat different layout,
although they operate with the same principles.
50. Function keys
(labeled F1 to F2) are programmable keys whose
functions depend on the program being used. The F1 key,
for example, is generally used by many programs as the
key to be pressed to find help or assistance about the
program’s features; the F2 key is sometimes used for
saving a file or document. The other function keys are
utilized for various other commands.
The alphanumeric keys occupy a large part of the
keyboard. This group provides standard letters and
numbers for typing purposes, as well as important
symbols or characters like the @ or # signs. The
alphanumeric keys are probably the most used keys on
the keyboard.
51. For arithmetic computations, the numeric keypad
serves as a single-location typing pad for faster input. It
contains numbers from 0 to 9, the keys and symbols for
the operations addition, subtraction, multiplication, and
division, as well as the Enter key for getting the result
There are also what are called modifier keys. By
themselves, they do or perform nothing when pressed.
However, in combination with other keys, they execute
something. Modifier keys include the Control key (Ctrl),
alternate key (Alt), Shift key, and Caps Lock key. For
example, pressing “C” while holding the Control key will
put highlighted text into computer memory; pressing a
letter while holding the Shift key will make the letter
uppercase.
52. Editing keys like the Tab key, Backspace key,
Insert key (Ins), Delete key (Del), Space bar, and
Enter key are usually used in word processing
programs to manage text. The Backspace key,
for example, can delete the character that was
just typed, while the Enter key serves as a
carriage return to provide a new line for a
document.
53. The Mouse and Other Pointing Devices
The mouse is an input and pointing device
that can be moved and manipulated by the user to
move a pointer across the monitor, point to an
object, file, or icon on the screen, or execute the
object. Like the keyboard, the mouse is also a
primary input device used to tell the computer
what to do.
Standard Mouse
- Scroll wheel
- left mouse button
- right mouse button
54. Touch Pad
This is a small, flat, and smooth panel that
is sensitive to light touch and pressure. By lightly
dragging your finger across the panel, you can
control the pointer on the screen. Left and right
buttons are placed at the bottom part of the
touch pad, making them carry out the functions
of a mouse. A touch pad is used, in place of a
mouse, in laptops and notebooks.
55. Joystick
This is a device used for arcade games. It
can be moved in various directions (up or down,
left or right) and in different angles. It has a
number of buttons for executing certain game
commands. Joystick can be used to point to an
object on the screen, move the object to a
particular direction, or have the object do
something.
56. Touch Screen Device
This enables the user to point to items or
execute commands just by touching points on
the screen. The screen treats the touch or press
as an input from the user and it responds
accordingly.
57. 1. This is a device used for arcade
2. This is a small, flat, and smooth panel that is
sensitive to light touch and pressure.
3. This enables the user to point to items or
execute commands just by touching points
on the screen.
4. It is an input and pointing device that can be
moved and manipulated by the user to move
a pointer across the monitor
Standard mouse
5-7
58. Other Input Device
Aside from pointing devices, there are also many other
input devices used for a variety of inputs. Among these are
Barcode Reader – This device reads variable patterns
of width bars inscribed on products. This is usually used in
supermarkets and stores to read and compute prices fast.
Optical Mark Reader – It reads pencil or ink marks
using reflected light. This is used in forms like the ballot during
elections, and during standardized test.
Scanner – This device reads a printed image and
produces a digital image in its place. Most scanners today can
capture all the colors of a printed image, thus, replicating the
image 100% and producing an exact electronic copy. The
image can then be manipulated in the computer using
appropriate software.
59. Processing devices
Processing devices are those that accept input from
corresponding devices and process and transform them
accordingly
The Central Processing Unit (CPU)
The central Processing Unit (CPU) is the heart and soul of
a computing machine. It is responsible for receiving, analyzing
and processing all instructions to the computer. The CPU is a
combination of arithmetic and logic units, as well as various
electronic circuits.
CPU of latest computers is typically compressed into a
single microchip known as the microprocessor. The
microprocessor controls the whole computer system. The speed
and efficiency of a computer depends on how powerful the
microprocessor is
60. Most microprocessor speeds today are measured in terms of
gigahertz (GHz) or billions of cycles per second.
Computer Memory
Computer memory can store information or data, but not
for the purpose of storage, but as the work area for processing
data.
When we speak of computer memory, just remember
these two types: ROM and RAM.
ROM is short for Read-Only Memory. All computers have ROM
because it is where important files for starting up the computer
are stored. The information in ROM goes with the corresponding
CPU and computer model. Thus, data in ROM cannot be
rewritten. The BIOS, or basic input/output system, is also stored
in ROM.
61. When you start your computer, the CPU begins to read the ROM and
starts executing instructions in it, which include instructions to power
up the monitor, do some checks, and give options to the user. Without
input from the user, the CPU just continues processing, and then
transfers control to the operating system (the main program that runs
a computer). With the operating system or other programs running,
the computer now utilizes RAM.
RAM, or Random-Access Memory, is a primary computer
memory that is utilized as a work area by the operating system and all
programs that run in the machine. RAM consists of memory locations
that have addresses, to which programs can refer to when they
execute instructions or find data or information.
Since RAM is a non-permanent storage that serves as a work
area, all data and information that are stored in it are lost or discarded
the moment the user power off the computer. Thus, with another
computer session, RAM is as clean as new, ready for new programs to
use it.
62. Buses, Slots, and Ports
Part of the job of processing is connecting
to and coordinating with various input,
processing, output, and even storage devices.
Buses, ports, and slots provide this functions.
Buses are groups of wires (8, 16, or 32
wires) that connect the CPU with RAM, slots,
and other devices. They are called buses
because they transport information from one
device to another.
63. Slots – are places inside the CPU housing where
users can insert specialized boards or cards, like
graphics boards or audio boards that enhance
the performance of gameplay or audio.
Ports – are sockets usually located at the rear of
the computer chassis where peripherals,
including input, output, and other devices, may
be added.
64. OUTPUT DEVICES
Output devices are devices that accept
processed information and convert them into
something people can understand. By showing
users the results of their inputs, they can respond
accordingly. If we cannot see any result or output,
the computers are no use.
The primary output device, which computer
users can never use without, is the monitor or video
terminal. Other output devices are the printers and
speakers.
65. The monitor or Video Terminal
The monitor, screen, or video terminal is
the primary output device and has been a
constant computer accompaniment, especially
since the dawn of personal computers.
In fact, most beginning computer users
think of the monitor as the computer itself, with
its amazing display of graphics and colors, much
like the popular television screen itself.
66. The monitor or screen is important for it
provides immediate visual output or result. For
example, a user typing a character would
immediately see that character on screen; while a
gamer making his spaceship go to the left of the
screen would immediately see that movement. This
way, feedback is fast and users can ponder their
next action.
Monitors come in various shapes, sizes,
forms, resolutions, color, and what-have-you.
The resolution of monitors refers to the total
number of pixels that is displayed on the screen,
with a pixel being a single dot on your screen.
67. While being LCD or CRT, or having a higher
or lower resolution can tell on a monitor’s
performance, it is the video adapter, which
powers the monitor, that has a greater impact.
Video adapters utilize Video RAM as a work area
for graphics and images. Consequently, a higher
Video RAM allows for greater graphics
capabilities. Video RAM of most computers now
comes at 128 MB to 512 MB.
68. Working with Hardware
The Inside of the Machine
We know that a typical machine consists of a CPU housed
inside a casing, a monitor, and input devices like a mouse and a
keyboard. The most important of these, however, is the CPU. Many
users are not very familiar with the inside of the CPU, and they just
assume that it will always work. It is quite practical, however, to be
familiar with the CPU’s insides.
• Power supply
• CD/DVD Rom
• Hard Disk
• MotherBoard
• Microprocessor
• Video Card
• Memory
