Testing program

1. A. Computer Basics
1.00 Examine the role of hardware
and software.
Unit Objectives:
1.01-1.04

2. What Is A Computer?
• An electronic device that receives
data, processes data, stores data, and
produces a result (output).
• A collection of electronic circuits,
which can be on or off (open or
closed).
– These two states of the circuit are
represented by two digits, 0 and 1.
• Called the binary system
• Combining bits (0 and 1), you can represent
any character or number.

3. Benefits of Using
Computers
• Error-free calculations
• Speed
• Flexibility
• Storage
• Consistency and repetition

4. What Is A
Computer System?
• Hardware: the • Software: the intangible
set of instructions that
tangible, physical tells the computer what to
equipment that can be do; know as programs or
seen and touched such software programs.
as: – Two types: application
and system software
– Computer Case programs
– Monitor • Data: information entered
– Keyboard and Mouse into the computer to be
– Disk Drive processed, which consists
– Speakers of the following:
– Text, numbers, sounds,
and images
• People: the users of the
computers who enter the
data and use the output.

5. Types of Computers
• Supercomputer: most powerful
– Used to do things like predict hurricanes and
navigate satellites
• Mainframes and minicomputers: used by
business and government to process large
amounts of information
• Personal computers: smaller and less
powerful than the other types of
computers

6. Personal Computers
• Desktop computer: designed to be used on
a desktop.
• Notebook/Tablet computer: designed to
be used on a desktop but still small enough
to be portable.
• Laptop computer: designed to be small
enough and light enough to be used on your
lap.

7. Additional Types
of Computers
• PDAs (Personal Digital Assistants): a handheld
device that is often used in conjunction with a
desktop or other PC.
– May have a special keyboard, some use
a pen or stylus for entering data
- Data can be transferred to a desktop or laptop computer
• Web TV: provides easy access to the Internet
without having to have a traditional computer.
– Enables you to connect to the Internet and usually
includes a keyboard or other device for entering and
selecting data.

8. Data Communications
• The technology that enables computers to communicate
• The transmission of text, numeric, voice or video data from
one machine to another.
• Popular examples:
– Internet, electronic messages (e-mail), faxes, and electronic or
online banking
• Four components:
– Sender: the computer that is sending the message.
– Receiver: the computer receiving the message.
– Channel: the media that carries or transports the message.
(telephone wire, coaxial cable, microwave signal, or fiber optic)
– Protocol: the rules that govern the orderly transfer of the
data sent.

9. Data Communications
• Network: when computers are connected to other
computers
– They can share information and sometimes hardware
(printers)
– Local Area Networks (LAN): computers connected
together in a relatively close location such as in the
same building or department.
• The data and software for these computers are stored on
a central computer called the file server.
– Wide Area Networks (WAN): when local area networks
are expanded to include several local area networks
within a city, state, region, territory, country, continent,
or the world.

10. System Components
• Central Processing Unit (CPU): the microprocessor, the brains of
the computer.
– Housed on a tiny silicon chip
– Chip contains millions of switches and pathways that help your computer
make important decisions.
• CPU knows which switches to turn on and which to turn off because it
receives its instructions from computer programs (software).
– CPU has two primary sections:
• Arithmetic/logic unit
• Control unit
• Arithmetic/logic unit (ALU): performs arithmetic computations
and logical operations; by combining these two operations the ALU
can execute complex tasks.
– Arithmetic operations include addition, subtractions, multiplication, and
division.
– Logical operations involve comparisons.
• Control Unit: is the “boss” and coordinates all of the CPU’s
activities.
– Uses programming instructions, it controls the flow of information
through the processor by controlling what happens inside the processor.
• We communicate with the computer through programming languages.
– COBOL, C++, or VisualBasic.net, HTML, Java Script for example.

11. System Components
Memory: found on the motherboard; short term and long term.
– Random Access Memory (RAM): memory on the motherboard
that is short term; where data, information, and program
instructions are stored temporarily on a RAM chip or a set of
RAM chips.
• When the computer is turned off or if there is loss of power, what
ever is stored in RAM disappears.
• This memory know as the main memory and is considered volatile.
• The computer can read from and write to RAM.
– Read-Only Memory (ROM): memory on the motherboard that
is long term; where the specific instructions that are needed
for the computer to operate are stored.
• This memory is nonvolatile and your computer can only read from a
ROM chip.
• The instructions remain on the chip regardless if the power is
turned on or off.
• Most common is the BIOS ROM; where the computer uses
instructions contained on this chip to boot or start the system
when you turn on your computer.

12. System Components
• Basic Controllers: on the motherboard, a
device that controls the transfer of data
from the computer to a peripheral device
and vice versa.
• Examples: keyboards, mouse, monitors, and printers.
• Generally stored on one single chip.
• Serial and Parallel Ports: used to connect
our peripheral devices to the computer;
usually one serial and one parallel port on a
computer.
• Serial devices transmit data one bit at a time.
– A modem may be connected to this port.
• Parallel devices transfer several bits at a time.
– A printer may be connected to this port.

13. System Components
• Universal Serial Bus (USB): a new
standard that supports data transfer
rates of up to 12 million bits per second.
– A single USB port can be used to connect up to
127 peripheral devices
– Expected to replace serial and parallel ports in
the near future.
• Expansion Slots: an opening on the
motherboard where a circuit board or
expansion board can be inserted.
– Examples: Additional Memory, video cards,
modem cards, and sound cards.

14. How Does A Computer
Process Data?
• PC system case – the metal and plastic
case that houses the main system
components of the computer.
• Central to all of this is the motherboard or
system board that mounts into the case.
– Motherboard: is a circuit board (a thin plate
or board that contains electronic components)
that contains many integral components.

15. Data Representation
• ASCII (American Standard Code for
Information Interchange): the most
popular and widely used standardized
coding system
• Byte: eight bits or combinations of ones
and zeros represent a character.
– MB-Megabyte or roughly 1 million bytes
– GB-Gigabyte or roughly one billion bytes

16. Input, Output, & Storage
Devices
• Input device: • Output device:
hardware that hardware that allows
your computer to
allows you to
communicate with the
communicate with user
your computer. • Storage device:
allows you to store or
retrieve information

17. Computer Input Devices
• Keyboard • Touch screen
• Mouse/Trackball • Bar code reader
• Joystick • Scanner
• Light pen • Microphone
• Pointing Stick • Graphics Tablet
• Touchpad • Digital Cameras

18. Computer Output Devices
• Monitor: screen • Speakers: allow
that display you to hear voice,
information such as music, and other
text, numbers, and sounds from your
computer.
pictures.
• Modem: allows you
– softcopy
to use your
• Printer: gives you computer to
information from communicate with
the computer in other computers.
printed form.
– Hardcopy

19. Three Types of Printers
• Dot Matrix • Laser
– Gives a printed image in a
pattern (matrix) of tiny – Best quality of
ink dots. printed documents
• Less expensive and not as • Laser beam and an
clear
ink toner cartridge
• Inkjet Printer are used to produce
– Better quality of printed the images.
document • More expensive
• Machine uses an ink
cartridge and a printing
• Quick
element to print a finer
image on the paper.

20. Storage Devices
• Magnetic storage devices use oxide-coated
plastic storage media called mylar.
– As the disk rotates in the computer, an
electromagnetic read/write head stores or
retrieves data in circles called tracks.
• Tracks are numbered from the outside to the inside
and as data is stored on the disk it is stored on one
of these numbered track.
• Each track is labeled and the location is stored in a
log on the disk known as a file allocation table (FAT).

21. Types of Storage Devices
• Hard Disk Drive: used to store data inside
of the computer.
– Magnetic platter that holds a large amount of
information in a form the computer can
understand.
• Accessing data is faster
• Amount of data that can be stored is much more than
what can be stored on a floppy disk.
• Size of Hard drive is measured in megabytes or
gigabytes.

22. Types of Storage Devices
• Floppy Disk: flat circles of iron oxide-coated
plastic enclosed in a hard plastic case.
– Most are 3 ½ inches and have a capacity to hold
1.44 MB or more of data.
• Zip Disk: capable of storing tremendous
amounts of information
- They are only the size of a 3 inch disk but can
hold as much as 1 gigabyte of data

23. Types of Storage Devices
• Magnetic Tape Drives: • Optical discs: use laser
used for making technology to read and
write data on silver
backup copies of large platters.
volumes of data. – CD-ROM (Compact Disk
– Very slow Read-Only Memory) can
– Can be used to replace store up to 800MB of
information/data.
data that may have
been lost on the hard – You can only read data
from a CD
drive
– You can store data on a CD
– look similar to audio only if you have a CD
tapes. Burner and writable CDs
– Holds more than Floppy (CD-R or recordable CD-
ROM)
– DVD (Digital Versatile
Disk) is the size of a
regular CD and can be
played in a regular CD or in
a DVD movie player.

24. Systems Software
• A group of programs that coordinate and control
the resources and operations of a computer
system.
– Enables all components of the computer system to
communicate.
• Operating System (OS): provide an interface
between the user or application program and the
computer hardware.
– Win 95/98/2000
– Mac System 6/7
• Utility programs: help you perform housekeeping
chores; complete specialized tasks related to
managing the computer’s resources, file
management, and so on.
• GUI (graphical user interface): graphical symbols
(icons) represent files, disks,
• programs, and other objects.

25. Application Software
• Programs that work with the OS software
to help you use your computer to do
specific types of work.
• Categories:
– Business
– Communications
– Graphics and Multimedia
– Education and Reference
– Entertainment and Leisure
– Integrated Programs

26. Business Software
• Word Processing • Database
– program that allows you – Lets you set up an
to create, edit, and
print text documents electronic filing
• Report, flyer, memo systems
• Spreadsheet – Enter text and
– Numbered Rows and numbers
Lettered Columns
• Find, search, and
– Intersection of them =
printer info in
cell
different ways
• Grade book, financial
info – Address book,
Card Catalog

27. Software
• Communications • Multimedia:
– Works with your combines text,
modems or network graphics, animation,
hardware and allows video, and audio.
your computer to • Clip art: graphical
communicate with other images to be added
computers. to documents
• Exchange computer
files and email • Desktop Publishing:
uses both pictures
• Graphics Software and words to give
– Uses pictures or images you the ability to
to help communicate create documents
messages.
– Newsletters and
brochures

28. Software
• Education & • Entertainment &
Reference Leisure
– Available on many – Fun
topics – Games and
– Help simulations
– Easier – Tests your skills
– Quicker – interactive
• Examples: AR,
Encyclopedia, etc.

29. Integrated Software
• Combine several • Examples:
software – MS Works
applications into – MS OFFICE
one program. – Lotus SmartSuite
– Include:
– Work Processing
– Spreadsheet
– Database
– Communication

30. Proper Computer Care
• Keep food and drinks away from the computer and
keyboard.
• Avoid dusty locations.
• Use a surge protector.
• Keep magnets Away.
• Do not block vents on the CPU.
• Avoid bright sunny locations.
• Do not move the computer while it is in use.
• Always exit programs properly.
• Use a virus check program on a regular basis.

31. Proper Diskette Care
• Do not remove from drives while drive in running
or light is on.
• Avoid contact with magnets and electromagnetic
fields.
• Keep disks stored in a clean, cool and dry place
with a protective cover.
• Keep protective metal slider in place.
• Use a virus check program on a regular basis.
• Avoid hot and cold locations.
• Make a back-up copy of your programs and files.

32. Proper CD ROM Care
• Keep CDs stored in a clean, cool and dry place
with a protective cover.
• Avoid touching the back side of the CD; to avoid
scratches.
• Avoid hot and cold locations.
• Make a back-up copy of your programs and files.
• Insert into CD ROM Drive properly; label facing
up.
• Only write on CD’s with a CD Marking Pen on a
label or the correct side of the CD.

33. Proper Care of Printers
• Avoid cold, hot, and dusty locations.
• Always use the correct ink or toner replacement.
• Always have the proper printer cable connected
to your computer.
• Never pull paper out of a printer in motion.
• Do not turn off the printer while printing.
• Read the instruction manual before operating a
printer.
• Always use the proper type of paper in your
printer.

34. How to Maintain your
Computer System
• Start a notebook of information on your system.
– Serial numbers
– Vendor support telephone numbers
– User IDs
– Date and vendor for each equipment and software purchase.
– Trouble log
• Periodically review disk directories and delete unneeded files.
• Make sure all plug-ins are secure at all times.
• Turn off the power and disconnect the equipment form the power
source before you open the inside of you computer.
• Keep surrounding area dirt and dust free.
• Back up files and data regularly.
• Periodically defragment your hard disk.
• Protect your system from computer viruses
• Learn to use system diagnostic programs

35. Ergonomics
• The science of designing equipment for a
comfortable and safe working environment.
• Proper Computer Ergonomics
– Sit up straight and lean forward slightly from the waist.
– Keep your feet flat on the floor.
– Your body should be about a hand’s length from the front of
the keyboard and centered with the keyboard.
– Keep your fingers on the home row keys and curved.
– Keep your wrists up, not touching the keyboard or desk.
– Focus your eyes on the book, copy or screen.
– Place all materials you will type on the right side of the
computer and supplies on the left side.
– Keep any items you are not using off your desk.
– Occasionally rest your eyes and take short breaks.
– Avoid lights that cause glare on the monitor.