Computing Fundamentals Module Lesson 4 Computer Software

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Computing Fundamentals ModuleLesson 4 Computer
Software

• Computer Literacy BASICS

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Objectives

• Distinguish between software and hardware.
• Explain how a computer software program works.
• Understand the steps involved in software
  development.
• Describe the difference between applications
  software and systems software.

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Objectives (cont.)

• Describe the three categories of systems
  programs.
• Describe operating systems for microcomputers,
  including network operating systems.
• Define a user interface.

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Objectives (cont.)

• Explain the difference between a command-line
  user interface and a graphical user interface.
• Understand the boot process a computer goes
  through when you start it.

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Vocabulary

• Algorithm
• Applications software
• Boot
• Graphical user interfaces (GUIs)
• Language translators
• MS-DOS
• Multitasking

• Network operating system
• Operating systems
• Software development
• Systems software
• Unix
• User interface
• Utility software

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Hardware vs. Software

• Computer systems consist of both hardware and
  software.
• Hardware has little value without software, and
  software cannot run without hardware to run it.

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What Is Hardware?

• Hardware refers to anything you can physically
  touch
• The keyboard and the mouse
• The monitor and the printer
• The motherboard and expansion cards
• All the other components in the computer case or
  attached to the computer

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What Is Software?

• Software consists of the instructions issued to
  the computer to perform specific tasks
• The software on a computer system refers to the
  programs that make the computer run.
• Software programs are lists of instructions in
  code that the computer understands that tell the
  computer what to do.

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How Software Programs Work

• A computer processes data by applying rules
  called algorithms.
• An algorithm creates a logical progression of
  steps needed to accomplish a task.

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An Algorithm to Solve a Household Problem Dirty
Laundry
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Software Development

• Software development is a multistep process that
  begins with a need to perform a task more
  efficiently using a computer
• First, the programmer breaks down the problem
  into a series of steps in an algorithm.
• The programmer may use a flowchart to show
  different paths the program will take.

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Software Development (cont.)

• Next, the programmer writes the steps in a
  computer programming language or code, using
  formal terms and syntax.
• Then the computer translates the code into
  machine language it can understand and uses the
  translated commands to execute a program.

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Debugging Software

• The software development process does not end
  when the computer executes the program.
• Errors in syntax or even spelling can cause
  problems and distort program results.
• Tests of the software find and fix bugs or
  errors in the code so it will run properly.

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Types of Software

• There are literally thousands of software
  programs you can buy, but all of them can be
  grouped into one of two categories
• Applications software
• Systems software

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Applications Software

• Application software consists of programs that
  were created to perform a specific task.
• Application software is also called productivity
  software.

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Applications Software (cont.)

• The most common types of application software are
• Word-processing programs
• Spreadsheet software
• Presentation software
• Database software
• Web browsers
• Games

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Systems Software

• Systems software refers to the programs that are
  used to manage computer system resources.
• Systems software coordinates and controls the
  resources and operations of the computer itself.
• The three categories of systems software are
• Operating systems
• Utility programs
• Language translators

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Operating Systems

• Operating systems provide an interface between
  the user and the computer.
• There are many brands and versions of operating
  systems.
• An operating system is designed to work with a
  specific processor.

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An Operating System Is an InterfaceBetween Users
and Computers
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Utility Programs

• Utility programs are designed to help perform
  housekeeping chores for the computer
• Manage the computers resources
• Perform file and folder management tasks
• Clean up unused files from the hard disk
• Defragment disk storage
• Copy files from one disk to another
• Back up data to disk or tape

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Language Translators

• Computers cannot read program statements in
  programming language format, such as Visual Basic
  or Java program statements.
• Language translator programs convert program
  language code into machine code that can be
  understood by the computer.
• Once converted to machine code, the program can
  be run and executed by the computer.

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Microcomputer Operating Systems

• If your computer is a Macintosh, you are probably
  using a Mac OS.
• If your computer is a PC or is PC compatible, you
  are most likely using one of these operating
  systems
• DOS
• A combination of DOS and Windows
• A standalone version of Windows

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Mac OS

• Macintosh computers were introduced by Apple
  Computer in 1984.
• Macintosh had one of the first GUI operating
  systems, with icons that represented programs,
  documents, and disks.
• This was also the first operating system to
  provide an on-screen help system.

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DOS

• IBM introduced its first PC in 1981. Its
  operating system was called DOS, which stands for
  Disk Operating System.
• DOS is a command-line interface operating system.
  The user had to enter commands at a screen
  prompt.
• It was a single-tasking operating system, which
  meant that only one program at a time could be
  executed.

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Windows

• Windows was Microsofts first GUI operating
  system, released in 1987.
• The first versions were called operating
  environments because they acted as a shell around
  the DOS operating system and worked in
  combination with DOS.

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Windows

• Applications installed on a Windows system
  appeared as icons that were activated by clicking
  them, similar to the Mac OS Finder interface.
• The earliest versions of Windows were labeled
  Windows 3.0, 3.1, and so on.
• The first true multitasking version of Windows
  was Windows 95, which also included support for
  networking computers.

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Windows

• Windows 98 improved on Windows 95 and offered
  Internet integration and support for the USB bus.
• Windows 2000 was an update to Windows 98 and
  Windows NT and included tools for Web site
  creation.
• The latest version is Windows XP, which provides
  increased stability and device recognition.

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The Windows XP Operating System
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Other Operating Systems

• Unix was developed by ATT and is another early
  operating system that is still used today.
• It is a portable operating system, which means it
  can run on any hardware platform.
• Variants of Unix include the freeware operating
  system Linux and IBMs AIX.

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Network Operating Systems

• A network operating system (NOS) is designed to
  allow multiple computers to be connected and talk
  to each other.
• The most popular networking operating systems
  include
• Microsoft Windows NT
• Novells Netware
• IBMs Warp Server

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User Interfaces

• You are probably familiar with the user interface
  of an operating system because it is what you see
  when you use the computer.
• The user interface determines how user friendly
  the operating system is.
• There are two commonly used types of operating
  system interfaces, command-line interfaces and
  graphical user interfaces.

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Command-Line Interfaces

• With this interface, you must type exact commands
  into the computer from a command prompt.
• You must memorize many commands and keywords.
• Command-line interfaces are not as user friendly
  as graphical user interfaces.

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Graphical User Interfaces

• Menu-based interfaces were easier to use,
  providing options so that commands did not need
  to be memorized.
• The breakthrough in ease of use came with the
  introduction of graphical user interfaces (GUIs).

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Graphical User Interfaces (cont.)

• Users manipulate on-screen icons to perform
  functions, usually with a mouse or other pointing
  device.
• Most of todays personal computers are equipped
  with some type of user-friendly GUI.

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Comparing User Interfaces
Graphical User Interface
Command-Line Interface
Icons representing programs or files
Command prompt
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Starting Your Computer

• When you start your computer, operating system
  commands are loaded into memory.
• Each operating system starts the computer in its
  own individual way.
• When you turn on a computer, you boot the system.
• POST (Power-on Self Test), a series of tests that
  check RAM and verify that the keyboard and disk
  drives are connected to the computer, runs when
  you start your computer.

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Starting Your Computer (cont.)

• Then the BIOS (Basic Input Output System)
  searches for the boot record. The hard disk drive
  C is typically the startup drive, so that is
  where the BIOS will look first for the boot
  record. BIOS is built-in software on a ROM chip.
  It contains all of the code that controls the
  monitor, keyboard, disk drives, and other
  components.

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Starting Your Computer (cont.)

• The boot record, which includes several files, is
  loaded into RAM. These files contain programming
  configuration instructions for hardware devices
  and software applications that you may have
  installed on your computer.
• Next, the software drivers are loaded. Drivers
  enable you to use your printer, modem, scanner,
  or other devices. Generally, when you add a new
  device to your system, drivers are installed for
  that device.

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Starting Your Computer (cont.)

• Next to be loaded is the GUI or graphical user
  interface, such as Windows XP. When loading the
  GUI, the operating system reads the commands for
  your desktop configuration. It also loads
  whatever programs you have previously specified
  into the Windows Startup Folder.
• If everything goes as it should, the GUI displays
  the desktop and the computer is ready to use.

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Summary

• Hardware refers to anything you can touch.
• Software is instructions that tell the computer
  what to do.
• Software is also called a program.
• A computer processes data by applying rules
  called algorithms.

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Summary (cont.)

• An algorithm creates a logical progression of
  steps needed to accomplish a task.
• Software development is a multistep process that
  includes writing the command code in a
  programming language, having the computer
  translate the code into machine language, and
  then debugging and testing the program.

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Summary (cont.)

• The two basic types of computer software are
  applications software, also called productivity
  software, and systems software.
• Systems software coordinates and controls the
  resources and operations of a computer system.
• Three major categories of systems software are
  operating systems, utilities, and language
  translators.

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Summary (cont.)

• Operating systems provide an interface between
  the user and application program and the computer
  hardware.
• Utility programs help users complete specialized
  tasks, such as file management.
• Language translators convert code written in
  English-based software programs into machine
  language.

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Summary (cont.)

• All computers have operating systems.
• Mac OS is used with Apples Power Macintosh
  computers and Power Macintosh clones.
• DOS was introduced with the IBM PC in 1981 and is
  a character-based operating system.

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Summary (cont.)

• Microsoft introduced the first version of Windows
  in 1987 this was an operating environment.
• Windows 95 was Microsofts first true
  multitasking operating system.
• Unix is a portable operating system.

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Summary (cont.)

• Network operating systems allow a group of two or
  more microcomputers to be connected.
• The user interface is the part of the operating
  system with which we are most familiar.
• The two most common user interfaces are
  command-line interfaces and graphical user
  interfaces.

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Summary (cont.)

• Most of todays computers come with some type of
  graphical user interface.
• Icons are symbols that represent documents,
  software programs, disks, and so forth.
• A graphical interface includes standard text and
  graphics so that data processed in one
  application program can be shared by other
  applications.