Transcript Slide 1 - Znanje.org

ITGS – Software Basic
Processing with Programs 1
Food for Thought:
• Recipe for food
• Precise steps
• How many steps
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ITGS – Software Basic
Processing with Programs 2
Food for Thought:
• One step to explain many actions
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ITGS – Software Basic
Computers – fast, smart machines
Computers – smart or intelligent
machines
but they perform only basic arithmetic
operations
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ITGS – Software Basic
Algorithm
Algorithm is set of step-by-step
procedures for accomplishing a task.
Programmers turn algorithms into
programs by adding details, testing
procedures and debugging – correcting
errors.
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ITGS – Software Basic
The Language of Computers 1
Every computer processes instructions
in a native machine language.
Machine language uses numeric codes
to represent the most basic operationsadding, comparing, moving numbers and
repeating instructions.
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ITGS – Software Basic
The Language of Computers 2
Early programs were written in machine
language.
Nowadays, programming languages are
like human languages.
High-level languages: C++, Java, Visual
Basic.Net
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ITGS – Software Basic
A translator program 1
Computer understands only machine
language. High-level languages are easy
for use for human.
High-level languages must be translated
to the zeros and ones of machine
language.
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ITGS – Software Basic
A translator program 2
A translator program converts the
English-like instructions to the zeros and
ones of machine language.
Translation process must be finished
before using program.
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ITGS – Software Basic
A translator program 3
A translator programs are divided:
- compiler – translates file (formed .exe
executive file). Complete translation
before the first run (execution).
- interpreter each time when its run
translate instruction. (instruction by
instruction)
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ITGS – Software Basic
Translation processes 4
Input
Program
(Source file)
Compiler
Output:
Program
(Exe file)
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ITGS – Software Basic
Translation processes 5
Input
Statement
(each)
Interpreter
Output:
Statement
(each)
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ITGS – Software Basic
Documentation
Software package includes printed
documentation
• Tutorial manuals
• Reference manuals (how to use
software)
• Help (printed, on CD, DVD, computer
or online)
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ITGS – Software Basic
Upgrading
New version
6.0
6.1
7.0
Update:
• New versions
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ITGS – Software Basic
Compatibility 1
No complete, universal software
standards exist in computer world.
Problem: program written for one type of
computer system may not work on
another.
Windows 9x
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ITGS – Software Basic
Compatibility 2
Software - Microsoft:
• DOS
• Windows
• Office (documents)
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ITGS – Software Basic
Disclaimers
Most programs works amazingly well but
not perfectly.
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ITGS – Software Basic
Vertical Market and Custom Software
Applications designed specifically for a
particular business or industry are called
vertical-market or custom applications.
(restaurant-management software,
medical-billing software, school evidence
software)
Cost far more then mass-market
applications.
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ITGS – Software Basic
Operating system 1
System software:
• Operating system (OS)
• Utility programs
• Links
• Compilers
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ITGS – Software Basic
Operating system 2
Operating system (OS):
• Part of system software
• Work behind the scenes
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ITGS – Software Basic
Operating system 3
Operating system communicating with:
• screens
• printers
• disk drives
• other peripheral devices
OS communicate with peripherals and
with user
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ITGS – Software Basic
OS Concurrent Processing of Jobs
Operating system - concurrent
processing of jobs :
Rapidly switching back and forth
between jobs (waiting for input, or
printer, …)
Time sharing:
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ITGS – Software Basic
OS Communicate
Operating system communicating with:
• screens
• printers
• disk drives
• other peripheral devices
OS communicate with peripherals
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Memory Management
Several jobs concurrently:
OS must keep track
• Divide memory
• Swap information between the
computer’s memory and external
storage devices (access time slower)
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ITGS – Software Basic
Data Management
Several jobs concurrently:
OS must keep track
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Programs and Data Drivers
Utility programs serve as tools for doing
system and repairs that aren’t
automatically handled by the operating
system.
Copy files, repair damaged data files,
translate files to different programs,
compress files, …
Operating systems invoke many utility
programs
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ITGS – Software Basic
Desktop Operating Systems 1
PC operating systems, created for the
Apple II, the original IMB PC and other
machines, looked nothing like today’s
Macintosh and Windows operating
systems.
It was OS a character-based interface.
A command line systems.
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ITGS – Software Basic
Desktop Operating Systems 2
Graphic display; is not limited to
displaying rows and columns of
characters, it can individually control
every dot on the screen.
The MAC OS a graphical user interfaceabbreviated GUI (gooey)
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Desktop Operating Systems 3
The first to market, the Macintosh was
eclipsed in the GUI operating system. At
the beginning MS Windows was a
program (shell) that put graphical face
on MS DOS. With Windows 95 MS
transforming Windows from an operating
system shell into full operating system.
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ITGS – Software Basic
Desktop Operating Systems 4
Hierarchical menus in Windows Mac OS
organization (frequently needed
commands into compact).
Pop-up menus
Context-sensitive menus
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Multiple-User Operating systems:
Unix and Linux
Unix operating system developed at Bell
Labs over a decade before the first PCs,
enables a timesharing computer to
communicate with several other
computers or terminals at one time.
UNIX is command line, character-based
operating system.
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Using a Linux GUI
Goal: GNOME, a shell that puts a
graphical desktop environment between
you and the Linux command-line
environment.
Tools: Linux, GNOME, OpenOffice
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Hardware and Software Platforms 1
Microsoft Windows XP (2001)
• Home edition; home users
• Windows XP Professional (business
users)
• Windows XP Tablet PC Edition (Tablet
PC-style notebooks)
• Windows XP Media Center Edition
(multimedia-enabled PCs)
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ITGS – Software Basic
Hardware and Software Platforms 2
Microsoft Windows XP is enhanced
version of Windows 2000 Professional.
Both Windows XP and Windows 2000
are technically successors to Windows
NT, not Windows 9x/DOS.
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ITGS – Software Basic
Hardware and Software Platforms 3
Microsoft Server 2003 server-based
counterpart to Windows XP successor to
the Windows 2000 Server product
family, runs on all sizes of Web servers.
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Hardware and Software Platforms 4
Microsoft Windows Millennium Edition.
(Windows Me)/Windows9x. The end of
the DOS–based Windows versions.
(Windows 3.1x; Windows 95; Windows
98;
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ITGS – Software Basic
Hardware and Software Platforms 5
Microsoft Windows CE.NET is designed
mostly for embedded connecter devices,
and a special versions of the OS,
handheld computers like the Pocket PC.
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ITGS – Software Basic
Hardware and Software Platforms 6
•Palm OS
•Mac OS X(20)
•Mac OS 9
•Linux, Sun Solaris and other UNIX
variants.
Linux is free, but doesn’t offer
applications programs as Windows
does.
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ITGS – Software Basic
Hardware and Software Platforms 7
Operating systems need application
software so they can do useful work.
Application software needs to be built to
any kind of platform.
Platform is combination of hardware and
operating system software.
Cross-platform applications (MS Office,
Photoshop, are available in similar
versions for multiple platforms.
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ITGS – Software Basic
Hardware and Software Platforms 8
Three general platforms:
• Windows
• Mac OS (graphic design, publishing,
music, video, multimedia)
• UNIX/Linux (servers and high-end
workstations)
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Hardware and Software Platforms 9
Three OS:
• Windows (Intel or compatible CPU)
• Mac OS (Power PC processors)
• UNIX/Linux (can run on many
hardware platforms, including Intel and
Power PC processors) but different
versions of Linux aren’t necessarily
compatible.
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Hardware and Software Platforms 10
Emulation, blurs the line between
platforms.
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Hardware and Software Platforms 11
Network vs. desktop
More time on the Web
Microsoft’s .NET strategy is a response
to the popularity of Java, a platformneutral computer language developed.
Program written in Java can run on
different OS.
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ITGS – Software Basic
Password
Changing letters
Name of hacker programs used for
getting in program
How to keep security of password?
(hardware, software)
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