Introduction to
Computers
Essential Understanding of
Computers and Computer
Operations
Topics
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The term “computer” 
Four basic computer operations 
Data and information 
Principal components of computer 
Data storage devices and usage 
Software 
The Internet & WWW 
What is a Computer?
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A programmable machine that inputs,
processes, and outputs information
An electronic device for storing and
processing data
Composed of hardware and software
Can exist in a variety of sizes and
configurations
Examples
What Do Computers Do?
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Input, Process, Output, & Store data
Input
Process
Store Data
Output
Input, Processing, Storage,
and Output Devices
What is Data?
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The raw material of information
Contain facts w/o interpretations
The information entered into, and stored
within a computer or file
Used by applications to accomplish tasks
Unprocessed information
E.g. text, numbers, images, audio, & video
What is Information?
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Contains meaning, knowledge, instruction,
communication, & representation of data
Result of processing, manipulating and
organizing data in a way that adds to the
knowledge of the person receiving it
The output of information systems
Flow of Computing
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Data  Processing  Information
Example
Pat Brown
1001 Jump Street
Shoreline, WA 98123
$25 per hour
40 hours
Retrieve data
Calculate weekly wage:
$25 X 40 hours = $1000
Send information to
output device
Principal Components of
Computer
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Input devices
System units
Storage (memory) devices
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Importance of Saving
Output devices
Input Devices
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Keyboard, mouse, scanner, & etc
System Units
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CPU (Central Processing Unit)
Random Access Memory (RAM)
Secondary Storage Devices
Central Processing Unit (CPU)
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Main processor of a computer that makes
everything work
Interprets & carries out the basic instructions
Performs all the instruction, logic, &
mathematical processing
Storage (memory) Devices
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Two types:
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Primary:
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Temporary memory for dynamic access by the
processor (CPU)
RAM (Random Access Memory)
Secondary:
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Primary & Secondary
For large data storage, e.g. hard disk drive
RAM is much faster than disk drives for
dynamically interacting with the processor
Random Access Memory
(RAM) – the Primary Memory
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Temporarily stores instructions and data waiting
to be processed by the processor
Memory units are measured in kilobytes,
megabytes, or gigabytes
1 kilobytes = 1,000 bytes
= 1,000 memory locations ≈ 1,000 characters
1 megabyte (MB) = 1 million memory locations
1 gigabyte (GB) = 1 billion memory locations
E.g. 512 MB = 512 million characters
1 MB can hold approx. 500 pages of text
Secondary Memory (Semipermanent)
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Magnetic Disks
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Optical Disks
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Hard disks, floppy disks, zip disks
CD-ROM, CD-R (Recordable), CD-RW, DVD
Flash Memory Cards
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USB flash drive: Small, lightweight, & large
storage capacity
Importance of Saving and
Saving Often
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When using an application, data is stored in
RAM temporarily
When the file, application, or computer
closes, the data in the RAM is erased
Where do I save the files?
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At the Lab: Removable disks such as floppy, zip,
or USB.
At home: Hard drive (C:\) or any removable disk.
Never remove a disk while the light flashes
Saving on an existing file replaces the old
data with new (Save vs. Save As)
Importance of Data Backup
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All secondary storage devices such as floppy
and hard drive disks eventually fail, and you
lose the data
Make backup files weekly, if not daily
If you have a computer, use the hard drive or
a removable disk as your backup
Otherwise, use the second removable disk
Output Devices
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Printers
Monitors
and more
Personal Computers
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PC, Mac, and other microcomputers
Desktop, Laptop, PDA
Windows, Mac OS, Linux, etc.
Increasingly more capable, portable,
affordable, and mobile
System Software
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Manages computer operations
Instructs computer how to perform functions of
loading, storing, and executing an application
software and how to transfer data
Examples: Windows, Mac OS, Linux, & etc.
Application Software
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Programs that tell a computer how to perform
tasks and produce information
Categories:
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Word processing
Spreadsheet
Database
Presentation graphics
Web and Internet access
Desktop publishing / image editing / multimedia
editing
The Internet and WWW
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The Internet is the world’s largest network
Uses:
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Send messages (e-mail)
Access a wealth of information
Electronic commerce
Online meeting
Access entertainment and multimedia
WWW (World Wide Web)
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The more popular component of the Internet
Web page: A document containing text, hyperlinks, images, &
other multimedia contents
Web site: A collection of Web pages
Communications Devices
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Modem
Network card
Router
Wireless modem, network card, & router