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ACS-1803-052 Introduction to Information Systems

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ACS-1803-052 Introduction to Information Systems Instructor: Kerry Augustine Hardware and Software Lecture Outline 2 Fundamentals of Information Systems, Sixth Edition – PowerPoint PPT presentation

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Title: ACS-1803-052 Introduction to Information Systems


1
ACS-1803-052Introduction to Information Systems
  • Instructor Kerry Augustine

Hardware and Software Lecture Outline 2
Fundamentals of Information Systems, Sixth
Edition Ralph Stair, George Reynolds
2
Principles and Learning Objectives
  • Computer hardware must be carefully selected to
    meet the evolving needs of the organization and
    its supporting information systems
  • Identify and discuss the role of the essential
    hardware components of a computer system
  • Identify the characteristics of and discuss the
    usage of various classes of single-user and
    multiuser computer systems

3
Principles and Learning Objectives (continued)
  • Systems and application software are critical in
    helping individuals and organizations achieve
    their goals
  • Identify and briefly describe the functions of
    the two basic kinds of software
  • Outline the role of the operating system and
    identify the features of several popular
    operating systems

4
Principles and Learning Objectives (continued)
  • Organizations should choose a programming
    language whose functional characteristics are
    appropriate for the task at hand, considering the
    skills and experience of the programming staff
  • Outline the overall evolution and importance of
    programming languages and clearly differentiate
    among the generations of programming languages

5
Principles and Learning Objectives (continued)
  • The software industry continues to undergo
    constant change users need to be aware of recent
    trends and issues to be effective in their
    business and personal life
  • Identify several key software issues and trends
    that have an impact on organizations and
    individuals

6
Why Learn About Hardware and Software?
  • Organizations invest in computer hardware to
  • Improve worker productivity
  • Increase revenue, reduce costs
  • Provide better customer service
  • Managers
  • Are expected to know enough about their business
    needs to be able to ask tough questions

7
Computer Systems Integrating the Power of
Technology
  • To assemble an effective and efficient system
  • You should select and organize components while
    understanding the trade-offs between overall
    system performance and cost, control, and
    complexity
  • Hardware objectives are
  • Subordinate to, but supportive of, the
    information system and the current and future
    needs of the organization

8
Introducing the Computer Chapter 2, Pages 64 - 81
- one def'n information processor capable
of performing electronically substantial
computations including numerous arithmetic or
logical operations without intervention by a
human operator   - basic architecture
CENTRAL INPUT -gt PROCESSING
-gtOUTPUT UNIT MAIN MEMORY
(internal)   AUXILIARY STORAGE (external)
9
Computer Components
  • Central processing unit (CPU)
  • Arithmetic/logic unit, the control unit, and the
    register areas
  • Arithmetic/logic unit (ALU)
  • Performs mathematical calculations and makes
    logical comparisons
  • Control unit
  • Sequentially accesses program instructions,
    decodes them, and coordinates the flow of data in
    and out of the ALU, registers, primary storage,
    and even secondary storage and various output
    devices

10
Computer Components (continued)
11
Processing and Memory Devices Power, Speed, and
Capacity
  • System unit
  • Houses the components responsible for processing
    (the CPU and memory)
  • All other computer system devices
  • Are linked either directly or indirectly into the
    system unit housing

12
Processing Characteristics and Functions
  • Clock speed
  • Series of electronic pulses produced at a
    predetermined rate that affects machine cycle
    time
  • Often measured in
  • Megahertz (MHz) millions of cycles per second
  • Gigahertz (GHz) billions of cycles per second
  • Physical characteristics of the CPU
  • Most CPUs are collections of digital circuits
    imprinted on silicon wafers, or chips, each no
    bigger than the tip of a pencil eraser

13
Memory Characteristics and Functions
  • Memory
  • Provides the CPU with a working storage area for
    programs and data
  • Rapidly provides data and instructions to the CPU
  • Storage capacity
  • Eight bits together form a byte (B)

14
Main Memory Into the cells in main memory we put
  - instructions   - data for the
instructions - both in electronic
form   Instructions for the CPU - tell it to
perform sequences of very basic
operations   e.g., add, subtract, multiply,
divide, move, store  
Every major problem that we want the computer to
solve  - must be broken down into a series of
instructions at this simple level - these are
the only kind of instructions that the computer
can actually execute
15
Sample Machine Level Program   Instruction for a
computer opcode address Opcodes (engineers
decide on these) 008 - clear accumulator and
add to it the contents of the main memory address
that follows this opcode 009 - add to the
accumulator the contents of the main memory
address that follows this opcode 010 - store
the result from the accumulator in the main
memory address that follows this opcode
example of an instruction 008 003  
16
Instruction is 008 003   008 - load into
accumulator in ALU 003 - whatever is in address
(cell) 3 in memory   Sample program for CPU and
its data program memory cell 0 008
003 1 009 004 2 010 005 data
memory cell 3 000 100 memory
cell 4 000 050 Instructions are
transferred, from memory into the CPUs control
unit, one by one, where they are placed in a
register and decoded by wires lets play
computer on board
17
Basic Workings (See VOD Lecture 1) The
CPU   Control Unit (registers)    Arithmet
ic / Logic Unit (ALU)   Main
Memory   (Primary Storage)    

Instruction Registry

Accumulator



0
1
008 003
009 004
2
3
010 005
100
4
5
50
18
Basic Workings (See VOD Lecture 1) The
CPU   Control Unit (registers)    Arithmet
ic / Logic Unit (ALU)   Main
Memory   (Primary Storage)    

Instruction Registry

Accumulator
008 003
100



0
1
008 003
009 004
2
3
010 005
100
4
5
50
19
Basic Workings (See VOD Lecture 1) The
CPU   Control Unit (registers)    Arithmet
ic / Logic Unit (ALU)   Main
Memory   (Primary Storage)    

Instruction Registry

Accumulator
009 004
100



0
1
008 003
009 004
2
3
010 005
100
4
5
50
20
Basic Workings (See VOD Lecture 1) The
CPU   Control Unit (registers)    Arithmet
ic / Logic Unit (ALU)   Main
Memory   (Primary Storage)    

Instruction Registry

Accumulator
009 004
150



0
1
008 003
009 004
2
3
010 005
100
4
5
50
21
Basic Workings (See VOD Lecture 1) The
CPU   Control Unit (registers)    Arithmet
ic / Logic Unit (ALU)   Main
Memory   (Primary Storage)    

Instruction Registry

Accumulator
010 005
150



0
1
008 003
009 004
2
3
010 005
100
4
5
50
150
22
The machine fetches instructions (from memory),
decodes and executes (in CPU) and stores results
of the execution (in memory) example of an
instruction for CPU 008 003   However, such an
instruction must be represented electronically,
ONLY in terms of or -   008 003 (base
10)   1000 0011 (base 2) --- -- (electronic
form) This is how the instruction looks in the
machine
23
Instructions at this level ( and -) are said to
be in machine language   Earliest programs were
written in machine language (first generation
language)   Then, a coding system was
developed   - each character on keyboard is
represented by a specific sequence of 0s and 1s
(ASCII or EBCDIC agreed upon coding
schemes)  
24
ASCII Table
  • ASCII Table
  • How each character on the keyboard is represented
    by eight 0s and 1s inside the computer according
    to an agreed upon coding system
  • http//www.newebgroup.com/rod/newillusions/ascii.h
    tm  

25
Processing Language Binary Example
American Standard Code for Information
Interchange (ASCII)
  • Types of Binary
  • Micro Computers
  • ASCII - 8 bit
  • Extended 8 bit
  • Mainframe Computers
  • EBCIDIC 8 bit
  • Other Types
  • Unicode 16 bit (used for international
    languages)

26
Processing Language Binary Example
American Standard Code for Information
Interchange (ASCII) 8 Bit (Std)
Extended Binary Coded Decimal Interchange Code
(EBCDIC) 8 Bit (IBM) Universal Character Set
(Unicode) 16 Bit
27
Processing Language
  • Binary or Machine Language
  • The language that all computers use
  • IT is expressed in 0s or 1s only (see below)
  • Binary utilizes Base-2 math to convert from
    normal characters to binary code (e.g. A 0100
    0001 in binary)

Binary Example
How a Computer Uses it
A 0100 0001
Byte (8 bits) Makes up one character
Bit A single 0 or 1
28
Related Terms Bit single digit - can be 0 or
1   Byte 8 bits side by side (moved around
addressed as a unit) 8 bits 1 byte Main
memory capacity -gt in bytes  
29
Memory Characteristics and Functions
30
How did a coding system make programming easier?
  • - now programs could be written in symbolic
    machine language (assembly language) because
    letters could be entered into a computer in 0s
    and 1s

31
  e.g., CLA X ADD Y (second generation
STO Z language) X Y Z ADDING
TWO NUMERS IN ASSEMBLY LANGUAGE A translation
program assembler, itself in machine language,
would translate this code into actual machine
language for the CPU
32
Translating Assembly Language
  • Programmer writes CLA X
  • Machine receives
  • 0100 0011 0100 1100 0100 0001 0101 1001
  • C L A X
  • (if there was no ascii we couldnt get this in)
  • - Assembler program translates this to
  • 1000 0011 (008 003) equivalent machine lang
    instr.

33
But, assembly language second generation - low
level   - one statement in assembly language
  translates into   - one statement in machine
language   A complicated, "real world" problem,
still had to be broken down into small steps for
the CPU    Then came third generation languages
(high-level) - one statement in
3GL   translates into   - many statements in
machine language
34
To program a complicated problem, we do not have
to think at the level of machine
language (translation program compiler or
interpreter translates 3GL to machine language)
  However, in a 3GL, we still have to tell the
computer both WHAT to do and HOW to do
it.   Different 3GLs  COBOL (business) FORTRAN
(scientific) BASIC PASCAL C JAVA - each
has different grammar suited to different
problems
35
Compilers and Interpreters
Compilers These highly-specialized software
applications are used to convert program
instructions (source code) into the machine code
(object code) prior to being loaded into a
computers secondary storage
Compiler Example
36
Program to add two numbers
  • Machine Assembly
  • Language Language
  • 1000 0011 CLA X
  • 1001 0100 ADD Y
  • 1010 0101 STO Z
  • X
  • Y
  • Z

37
Program to add two numbers
  • FORTRAN 3rd Generation Language
  • Z X Y
  • (will be translated to mach. language by FORTRAN
    compiler)
  • COBOL 3rd Generation Language
  • ADD Y TO X GIVING Z.
  • (will be translated to mach. language by COBOL
    compiler)
  • We tell computer WHAT to do but not HOW to do it
    NON-PROCEDURAL

38
Fourth Generation Languages   - much more
user-friendly - we tell computer WHAT to do but
not HOW to do it NON-PROCEDURAL - how is a
4GL developed? (the "Averager")   - exist only
for specific problems / uses   Different
4GLs DOS dBASE SQL
39
  • - We can also call common application software
  •   - Word processing
  • - Spreadsheets
  • - Web browsers
  • - Multimedia programs
  • Fourth generation (non-procedural) software WHAT
    to do not HOW but they are not, properly,
    languages
  • - Sometimes called productivity tools
  • They use a GRAPHICAL USER INTERFACE

40
Programming Languages Generations Summary
Programming Languages These languages are used to
write program instructions and have evolved over
time making them more powerful, easier to read
and write, and more natural language-focused
Generations of Programming Languages
mid 1950s
1940s
1950s
1970s
1990s
1st Machine Binary
2nd Symbolic Use of symbols
3rd High-Level Use English like words for
procedures
4th Outcome Oriented Use outcome focused words
5th Artificial Intelligence Natural
language (spoken English)
41
Procedural and Non-procedural Computing
  • PROCEDURAL
  • - Need to tell the computer WHAT you want and HOW
    to do it (how to proceed)
  • - Need to have an algorithm for the problem
  • (sequence of logical steps necessary to solve the
    problem)
  • -Need to code the algorithm in a procedural (3rd
    Gen) language

42
Finding the Average of Numbers
  • The Algorithm
  • NNum 0 SumNum0
  • While there are numbers to read
  • Read a number
  • Add 1 to NNum
  • Add the number to SumNum
  • End While
  • Average SumNum / NNum
  • Print Average is , Average

43
Coding the Algorithm
  • The algorithm (set of steps) will now be coded in
    a procedural language C language?
  • This program tells the computer HOW to find the
    average
  • The program will be compiled to machine language
    and run on a computer

44
Finding Average in Non-procedural Language
  • AVERAGE 232, 452, 554, 667, 932, 122
  • thats it
  • who told the computer how to do this??
  • OR
  • Type in the numbers into a box
  • Click a button for Average (using GUI)

45
Popular Programming Languages
46
Programming Languages More Recent High-Level
  • Object-Oriented Programming (OOP)
  • These languages allow programmers to group data
    and program instructions together into modules
    (objects) that can be manipulated by a programmer
    (e.g Java or C). Characteristics of OOPs
    programming include
  • Encapsulation grouping pieces of data together
  • Inheritance as one class of objects are
    defined, all other objects with the same
    characteristic are automatically defined
  • Event-driven these programs are driven by
    events (e.g. a button being pushed) instead of
    following sequential logic

Visual Languages These languages take advantage
of graphical user interfaces (GUIs) allowing
additions of visual objects (e.g. buttons) with a
few clicks versus coding the object pixel by
pixel
47
Programming Languages Visual Language example
48
Programming Languages Web Development
Web Development Languages These languages are
used to develop Web pages and operations using
both static and dynamic content
Hypertext Markup Language (HTML) This is a
text-based file format that uses a series of
codes, or tags to set up a document. Programming
can be done either in native HTML or using an
HTML editor that generates the HTML code from
visual renderings
Extensible Markup Language (XML) XML was
designed to be used as a Web page construction
tool allowing users to create markup tags or
build database queries. It is a powerful
language used to create database fields for
accessing databases from Web pages and can be
read using a browser called an XML parser
49
Programming Languages Common HTML Tags
50
Programming Languages Web Development
Dynamic Content Markup languages are used for
laying out or formatting content, while dynamic
languages are needed to provide animation or
dynamic (changing) content
  • Dynamic Languages
  • Several languages are available for creating
    dynamic content such as
  • Java Invented by Sun Microsystems, this
    language is very popular for use in Web pages to
    provide animation (applets) or for writing more
    general purpose programs allowing them to run on
    all platforms
  • ActiveX Invented by Microsoft to perform the
    same function as Java but is designed to run
    under MS Windows
  • Scripting Languages (JavaScript) this language
    allows the direct imbedding of program functions
    (scripts) into HTML pages and is frequently used
    for validation of user input (e.g. validate
    postal code)

51
Programming Languages A Java Enabled Web Page
52
Processing Automated Development Environments
Computer-aided Software Engineering (CASE) These
are automated software tools used by systems
developers to design and implement information
systems. These tools continue to evolve and come
in many types
53
Automated Development Environments A CASE Tool
54
Automated Development Environments CASE
Influence
Influence of CASE Tools on Individuals CASE can
dramatically increase the speed and quality of
system development and maintenance while having a
strong impact on culture. For IS managers it is
commonly positive due to higher quality and lower
risk, while for IS developers it is often
negative for fear of replacement
55
Microcomputer System
Output Device Monitor
Input Device Keyboard
Processing Device The System Unit
56
  • The Microcomputer e.g, PC or Apple
  • How, specifically, are the computing principles
    that we saw here, implemented in a PC?
  • microprocessor (chip) is the CPU
  • much elaborate, user-friendly software
  • - consists of system unit (box), monitor
    (screen), keyboard, mouse, printer
  •  
  • In the system unit
  •  
  • - motherboard, disk drives, CD-ROM drive, cards,
    cables, power supply
  •  

57
Motherboard - Main circuit board
microprocessor (CPU chip), RAM (Random
Access memory - main memory), buses,
cards   - Intel microprocessor chips (past and
present)   8088, 8086, 80286, 80386, 80486,
Pentium   -speed in MegaHertz (Million of
vibrations per second) or GigaHertz (1024 MHz)
-all processing (calculations) done in the
microprocessor
58
Processing Mother Board Example
Power Supply
CPU (Micro Processor)
ROM
Expansion Slot
CD/DVD Drive
RAM
59
  • - RAM main memory chips 1-2 GB .
  •  
  • Into RAM goes the Operating System, Application
    Software, Data
  • ROM (Read Only Memory) burned-in programs to
    start up the computer
  • - Buses (multi-lane highways) carry instructions
    from memory to microprocessor and back
  •  
  • - Expansion Cards circuit boards that plug into
    expansion slots on the motherboard
  • link peripheral equipment (printers, disks) with
    motherboard
  • - at the back of the cards are ports

60
In addition to CPU and memory, we have other
parts of a computer system Computer
Storage   Primary (Internal) Storage - main
memory - stores instructions and data that are
being worked on by the CPU - contents
erased when power off   Secondary (External)
Storage (p. 68 )   - more permanent -
magnetic disk, tape - optical storage
61
Magnetic Disk   - floppy or hard disk   -
platters one below other - each platter has
tracks - data stored along tracks - info.
picked up by read / write heads   - we take
software and data from disk to main memory   -
disk allows direct access as opposed to tape
which is sequential   - 1024 Megabytes 1
Gigabyte
62
Optical Storage   - CD compact disk - laser
light instead of magnetic form - can store much
more data in same amount of space   - may
take longer to retrieve CD-ROM - can store
encyclopedias - read only   WORM, or
Rewriteable optical disks  
63
Disk drives   - hold the actual disks - floppy
or hard - hard disk stores more info and info can
be retrieved faster - before a disk is ready for
storage it must be formatted by the operating
system   Optical (CD) drives, DVD drives   -
for compact disks, digital video disks - for
CD-RW, CD-R, CD-ROM optical disks - considerable
application software is now purchased on
CD-ROM  Memory Sticks (flash drives) (use USB
port)  - few moving parts
64
  • Parts of a Microcomputer System Unit
  • Keyboard
  •   - press key, the character's ASCII code is sent
    down
  • Monitor
  • - CRT, VDT (video display terminal)
  • - had CGA, EGA, VGA, Super VGA
  • - more colors, dots closer together
  • Printer
  • - Impact or non-impact
  • Dot matrix (old)
  • Ink jet
  • Laser
  • Mouse
  • - for use with Graphical User Interfaces (GUIs)
    on the screen

65
Input Devices
  • Devices used to input general types of data
  • Personal computer input devices
  • Speech recognition technology
  • Digital cameras
  • Touch-sensitive screens
  • Optical data readers
  • Magnetic ink character recognition (MICR) devices
  • Pen input devices
  • Magnetic stripe card
  • Radio Frequency Identification

66
Input Devices (continued)
67
Output Devices
  • Display monitors
  • Used to display the output from the computer
  • Plasma display
  • Uses thousands of smart cells (pixels) consisting
    of electrodes and neon and xenon gases that are
    electrically turned into plasma to emit light
  • LCD displays
  • Flat displays that use liquid crystals
  • Organic light-emitting diodes (OLEDs)
  • Use a layer of organic material sandwiched
    between two conductors

68
Output Devices (continued)
  • Printers and plotters
  • Two main types of printers are laser printers and
    inkjet printers
  • Plotters are a type of hard-copy output device
    used for general design work
  • Digital audio player
  • Can store, organize, and play digital music files
  • E-books
  • Digital media equivalent of a conventional
    printed book

69
Output Devices (continued)
  • Modem
  • modulator / demodulator
  • needed for talking to another computer by phone
  • changes the form of information from and - in
    a computer to a continuous wave form used on a
    phone line and back to and - on receiving end
  • - can be internal or external internal is on a
    card and plugs into motherboard
  •  

70
Software
71
Software   - like a cassette and the song on
it   - software instructions in electronic form
(programs)   - data also in "soft" form, but
not called software System and Application
Software   System Software (p.84)
"behind-the-scenes " programs which help the
computer to operate Application software
(p.94) programs intended to solve problems
outside of the computer itself  
72
Systems Software
- Most important category in system software is
the Operating System   e.g., DOS, Windows 2000,
Unix, Mac OS/X p. 84-92 text -gt make brief
notes -tasks - finding disk space
-allocating memory to user programs
- Other system software Utility Programs (p.
93) e.g., Anti-virus make a list
73
Operating System Software
  • Set of programs that controls computer hardware
    and acts as an interface with application
    programs
  • Can control one computer or multiple computers,
    or
  • Can allow multiple users to interact with one
    computer
  • Combinations of OSs, computers, and users
  • Single computer with a single user
  • Single computer with multiple users
  • Multiple computers with multiple users
  • Special-purpose computers

74
Operating Systems (continued)
  • Activities performed by the operating system
  • Perform common computer hardware functions
  • Provide a user interface and input/output
    management
  • Provide a degree of hardware independence
  • Manage system memory
  • Manage processing tasks
  • Provide networking capability
  • Control access to system resources
  • Manage files

75
Operating Systems (continued)
  • Common hardware functions
  • Get input from keyboard or another input device
  • Retrieve data from disks
  • Store data on disks
  • Display information on a monitor or printer

76
Operating Systems (continued)
  • User interface and input/output management
  • User interface
  • Allows individuals to access and command the
    computer system
  • Command-based user interface
  • Requires that text commands be given to the
    computer to perform basic activities
  • Graphical user interface (GUI)
  • Uses icons and menus displayed on screen to send
    commands to the computer system

77
Operating Systems (continued)
  • Hardware independence
  • Application program interface (API)
  • Allows applications to make use of the operating
    system
  • Memory management
  • Allows computer to execute program instructions
    effectively and to speed processing

78
Operating Systems (continued)
  • Processing tasks
  • Multitasking
  • More than one program can run at the same time
  • Time-sharing
  • Allows more than one person to use a computer
    system at the same time
  • Scalability
  • Ability of the computer to handle an increasing
    number of concurrent users smoothly

79
Operating Systems (continued)
  • Networking capability
  • Allows computers in a network to send and receive
    data and share computing resources
  • Access to system resources and security
  • Protection against unauthorized access
  • OS establishes a logon procedure
  • File management
  • Ensures that files in secondary storage are
    available when needed and that they are protected
    from access by unauthorized users

80
Current Operating Systems
  • Microsoft PC operating systems
  • Windows XP
  • Windows Vista
  • Windows 7
  • Apple computer operating systems
  • Wintel
  • Snow Leopard (OS X v10.6)
  • Linux
  • Red Hat Linux
  • Caldera OpenLinux

81
Software for the Microcomputer
  • Operating System (p. 84)
  • PC DOS, Windows 3.1, Windows 2000, XP, Vista.
    W7 Windows NT, OS/2, Linux
  • Unix op. system - multi-user, multi-tasking
  • several screens keyboards into one system unit
  •  Apple System 7.5, Mac OS,

82
Operating System Interfaces
Interfaces After boot up, the computer provides
an interface for the user or programmer to
interact with it. Different operating systems
use different types
  • Common Interface Type
  • Command-based interface this type requires a
    user to type commands to perform basic functions
    (i.e. DELETE File1 means erase File1)
  • Menu interface this type presents a list of
    options from which the user selects to invoke a
    command or system operation
  • Graphical user interface (GUI) the most common
    interface today that uses pictures, icons, and
    menus to send instructions form the user to the
    computer system

83
Common Operating Systems
84
Operating Systems - Utilities
Utilities Programs that manage computer
resources and files and may be included in the
operating system or purchased separately as
needed
85
Application Software - non-procedural - for
specific application purposes - runs under a
specific operating system   KEY TYPES OF SOFTWARE
(p. 96)  1. Word Processing   - e.g., Word,
WordPerfect - contain desktop publishing
features  2. Spreadsheets - electronic
worksheet with rows and columns   - some numbers
are entered and others ar calculated through
formulas   - can do "what-if" analysis decision
support   - e.g., Excel, Lotus
86
Application Software Examples
87
3. Data Management Software   - keep records
of data in a file - extract records that satisfy
certain conditions - sort the data, produce
reports   Storing "real world" information in a
computer     more on data management soon 
88
  • 4. Accounting Software
  • electronic bookkeeping
  • flexible report generator
  • smaller business Simply Accounting, Great
    Plains
  • Accounting, QuickBooks
  • - larger ACCPAC PLUS, ACCPAC for Windows
  •  
  • 5. Specific Industry Systems
  • fit the information needs of specific businesses
  • e.g. - manufacturing software for a window
    company
  • - appointment book for a dentist's office
  • - software to manage a golf course
  • such packages may connect to existing accounting
    software
  • PLUS MANY, MANY OTHER TYPES

89
Open Source Software
Open Source A special class of software that
includes operating systems, application software,
and programming languages in which the source
code (the actual program code) is freely
available to the general public for use and/or
modification
  • Popular Open Source Applications
  • A number of mainstream open source applications
    can be found across many organizations. Here are
    just a few
  • Operating systems Linux
  • Web browsers Mozilla
  • Web servers Apache
  • E-mail processing Sendmail
  • Internet domain naming service BIND
  • Secure connection standard - OpenSSL

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  • Classification of Computers p. 77-78
  • Supercomputers largest, most powerful,
    perform parallel processing
  • Mainframes central, many dumb terminals
  • Minicomputers smaller mainframes
  • Microcomputers can be networked others
    fill-in, e.g., portable computers p. 78

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Types of Computers - Generations of Computing
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Types of Computers Supercomputer Workstations
  • These are the most powerful and expensive
    computers on earth and are
  • built and used for one specific purpose (e.g.
    weather forecasting)
  • thousands of times more powerful than a
    high-powered PC

Workstations
  • A special class of computers designed for
    individuals, with high power to perform
    specialized tasks fits on the desktop and used
    for
  • extremely data-intensive processing (i.e. design
    or financial analysis)

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Types of Computers Mainframe Midrange
Mainframe Computer
  • These are the backbone of large corporate and
    government computing and
  • can process very large amounts of information
  • support hundreds or thousands of users
    simultaneously
  • These are smaller versions of mainframe computers
    used in smaller organizations and for multiple
    functions and
  • supports tens to hundreds of users
  • used as servers including web, database, and
    application servers

Midrange Computer
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Types of Computers Microcomputers
Personal Computers
PCs come in desktop and portable models and are
commonly used for personal and business uses,
they are generally low cost and have many
powerful applications written for them
Network Computers
A network computer is a microcomputer with
minimal memory and storage, designed to connect
to a network, especially the Internet, using
resources provided by servers at low cost
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Types of Computers - Microcomputers
Portable Computers These smaller, lighter weight
computers are designed to enable mobile
processing
Notebook A lightweight PC designed to be
portable with sufficient battery power to be
useful
Tablet PC A small PC with a removable screen that
can be used as a writing tablet with a stylus
Handheld Computer Small computers that can be
carried on the body including PDAs, cell phones,
etc.
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Computer Hardware Equipment Categories
Input The act of entering information into a
computer using a device that is best suited for
the format of the data (i.e. a keyboard for
character information)
Processing Transforming inputs into outputs by
use of highly specialized computer components
that are integrated to communicate with input and
output devices
Output The act of receiving information from a
computer using the device that best suits the
application (i.e. a printer for a memo)
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Summary
  • Hardware
  • The physical components of a computer that
    perform the input, processing, storage, and
    output activities of the computer
  • Software
  • Consists of programs that control the workings of
    the computer hardware

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Summary (continued)
  • Operating system (OS)
  • Set of computer programs that controls the
    computer hardware to support users computing
    needs
  • Manages tasks to allocate computer resources
    through multitasking and time-sharing
  • Application software
  • Applies the power of the computer to solve
    problems and perform specific tasks
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