SOFTWARE 3 Chapter

Chapter Topics 3.1 System Software 3.2 Common Features of the User Interface 3.3 Common Operating Systems 3.4 Application Software 3.5 Word Processing Software 3.6 Spreadsheet Programs 3.7 Database Software

3.1 System Software The Power behind the Power

Application Software System Software Software developed to solve a particular problem for users Either performs useful work on a specific task Or provides entertainment We interact mainly with this software System Software Enables application software to interact with the computer Helps the computer to manage its own internal and external resources

System Software has 3 basic components Operating System —The principal component of system software Device Drivers — Help the computer control peripheral devices Utility Programs — Used to support, enhance, or expand existing programs in the computer

Operating System (OS) Low-level, master system of programs to manage basic computer operations Every general-purpose computer must have OS to run other programs OS allows users to concentrate on applications rather than on complexities of the computer Each application program is written to run on top of a particular OS Some OS functions: booting, CPU management, file management, task management, security management

Booting The process of loading an OS into the computer’s main memory Booting involves four steps: Turn the computer on Test the main memory, CPU, and other hardware Basic Input/Output System (BIOS) programs are copied to main memory BIOS contains instructions for operating the hardware The computer needs those instructions to operate the hardware and find a copy of the OS Boot program obtains the OS and loads it into computer’s main memory

Central Processing Unit (CPU) Management Supervisor is the software that manages CPU Remains in memory while the computer runs Memory Management OS keeps track of memory locations to prevent programs and data from overlapping each other Swaps portions of programs and data into the same memory but at different times

File Management A file is either a The file system arranges files in a Data File: a named collection of data Program File: a program that exists in a computer’s secondary storage The file system arranges files in a hierarchical manner Top level is directories (folders) Subdirectories come below folders Find files using their pathname. Example: C:/MyDocuments/Termpaper/section1.doc

Task Management Computers are required to perform many different tasks at once—to do task management Task: An operation such as storing, printing, or calculating Multitasking: Handling more than one program concurrently Example: You do word processing while playing music on your computer OS directs processor to alternate time on each program until processing is complete

Security Management Operating Systems permit users to control access to their computers Users gain access using an ID and password You set the password the first time you boot up a new computer After that, when you boot up, you’ll be prepared to type in your user name and password

Device Drivers Utilities Specialized software programs that allow input and output devices to communicate with the rest of the computer system When you buy a computer, many device drivers come with the system software Device drivers also come with new hardware (on CDs/DVDs) or can be downloaded from the manufacturer’s website Utilities Service programs that perform tasks related to the control and allocation of computer resources Some come with the OS, others can be bought separately like (e.g., Norton SystemWorks, McAfee Utilities)

3.2 Common Features of the User Interface

Graphical User Interface (GUI) Allows you to use a mouse or keystrokes to select icons and commands from menus Three main features of GUI are desktop, icons, and menus Desktop: The system’s main interface screen Icons: Small pictorial figures that represent programs, data files, or procedures Menus: Lists of built-in commands and/or options from which to choose

Most Operating Systems have the following: Title Bar: runs across the top of the display window Menu Bar: shows the names of the pull-down menus available Toolbar: Displays menus and icons representing frequently used commands Taskbar: The bar across the bottom of the Windows screen that contains the Start button A window: A rectangular frame on the computer screen through which you can view a file of data or an application

3.3 Common Operating Systems

Two principal systems are Platform The particular processor model on which a computer system is based Two principal systems are Mac platforms—run Apple Macintosh PC platforms—run Microsoft Windows (e.g. XP, Vista, 7) Some legacy systems still used—outdated but still functional DOS (Disk Operating System) Original Microsoft OS—hard-to-use command-driven user interface

3.4 Application Software

Types of Application Software (Not standard) Entertainment Games Education Encyclopedias learning programs Productivity Word processing Spreadsheets Databases Specialized uses Financial Drawing & painting Video editing Animation

3.5 Word Processing Software

Word Processing: uses computers to create, edit, format, print, and store text Microsoft Word best known Others: Corel WordPerfect, Apple iWork Pages, Google Apps, Open Office, Zoho Writer

Editing Documents—Making alterations in content Inserting: adding text to documents Deleting: removing text from documents Find & Replace Find: lets you go straight to any text in your document Replace: lets you automatically replace it with something else Cut, Copy, & Paste Select the text you want to move Copy (or cut) to clipboard, then paste in new location

Spelling Checker: tests for incorrectly spelled words [Note: Do not rely on spelling and grammar checkers to be 100% accurate!] Grammar Checker: highlights poor grammar, wordiness, incomplete sentences, and awkward phrases Thesaurus: offers suggestions for alternative words with the same meaning

3.6 Spreadsheet Programs

Spreadsheets: to create tables and financial schedules Enter data and formulas into rows and columns on screen Programs; Microsoft Excel, Corel Quattro Pro, Lotus 1-2-3 Organized into columns and rows on a worksheet Labels are descriptive text Cells are where a row and a column meet Cell address is the position of the cell Range is a group of adjacent cells Values are numbers or dates entered into a cell See Microsoft Excel

Analytical Graphics: Creating Charts Spreadsheets allow you to automatically create graphs Analytical graphics: graphical forms that make numeric data easier to analyze Examples of types of analytical graphics: Column charts Bar charts Line graphs Pie charts Scatter charts

3.7 Database Software

Database: structured collection of interrelated files in a computer system Database software: sets up and controls the structure of a database and access to data Principal microcomputer databases: Microsoft Access, Corel Paradox Benefits databases: Data redundancy is minimized Data is integrated and stored in a structured fashion Data in databases has more integrity Data may include text, numbers, and graphics

Relational database: data organized into related tables Each table contains rows (records) & columns (fields) Key is field used to sort data Most frequent key field is social security number Tables with the same key field are linked together Querying and displaying records Database software offers a quick way to locate records Saving, Formatting, Printing, Copying, Transmitting Can save results, format them in different ways, print as reports, copy to other documents, & transmit as email