Friday, March 18, 2011

Using the Computer and Managing Files: Chap1-Less2

Introducing Software Concepts

Software can be defined as a set of programs that are used to operate computers and related devices. Software consists of a set of instructions written in various programming languages, such as C, Java, and C++.
Software can be classified into two main categories:
Operating System Software
Application Software



An operating system performs various system-related functions, such as handling files, managing computer memory, and communicating with the input/output devices. In addition, the operating system also acts as an interface between software applications and various input devices, such as the keyboard and the mouse. Operating systems, such as Windows 7, Windows Vista, Unix, Linux, and Novell Netware are available today. The operating system interface is of two types:

  • Character User Interface (CUI): It requires a user to type certain commands to perform operations, such as opening and deleting a file. For example, DOS operating system.
  • Graphical User Interface (GUI): It consists of various user-defined elements, such as windows and menus. The most commonly used GUI operating systems are Microsoft Windows and Apple Macintosh.
Application software is designed to perform a specific task according to user specifications. Some of the examples of application programs are:

  • Word Processors: They enable you to create, edit, format, and print documents such as letters, reports, and even Web pages. Some of the common word processing applications are Microsoft Word, Lotus WordPro, and Word Perfect.
  • Spreadsheets: They enable you to perform calculations based on predefined formulas and generate reports, graphs, and balance sheets. Some of the common spreadsheet applications are Microsoft Excel and Lotus 123.
  • Database Management System (DBMS): It enables you to store and retrieve large volumes of data. DBMS is used in various fields, such as airlines, railways, hospitals, and universities. A variety of DBMS software is available in the market, such as MS Access, DBASE and FoxPro.
  • Accounting Applications: They enable you to perform accounting operations, such as generating trial balance, profit and loss statements, balance sheets, and so on. The common accounting applications are Sage, ACCPAC, and Tally.
  • Web Browsers: They enable you to view Web pages on a Web site and search information on the Internet. The Internet is a public and global communication network that can be used to access a Web site, such as www.google.com. Some of the common Web browsers are Internet Explorer, and Mozilla, Google Chrome
Software Development Phases
Analysis: This stage involves the process of determining user requirements. These requirements are then studied to design the appropriate software application.
Designing: This stage involves creation of an outline or a blue print of the software application. Various design documents are prepared in the process of designing, which help formulate the structure of the software.
Coding: This stage involves creation of set of computer programs according to the design documents prepared to develop the required software application.
Testing: This stage involves evaluation of the computer program developed in the previous step. The software application is tested in entirety or by dividing it into small parts.
Implementation: This stage involves installation and deployment the software application at the client location.
Factors Affecting the Performance of a Computer
The performance of a computer depends on the following factors:
  1. CPU Speed: The entire design of the PC is based on the microprocessor chip or the CPU.
  2. Clock Speed: The components in a computer are designed to operate in perfect synchronization. To       do this, they need a time keeper.
  3. RAM Size: The RAM size is an important parameter in determining the size and complexity of operations that a computer can handle thus affecting the performance of the computer.
  4. Hard Disk Speed: The speed of the hard disk also affects the performance of the computer. The speed of the hard disk can be determined through disk access time. The disk access time is the time required for storing and retrieving the data from and to the hard disk.
Types of Computers
Computers can be classified into the following categories based on various features, such as size and speed:

Toshiba NB505-N508BL 10.1-Inch Netbook (Blue)ASUS Eee PC 1001PX-EU27-BK 10.1-Inch Netbook (Black)Toshiba Mini NB255-N245 10.1-Inch Netbook (Black Oynx)Apple iBook G3 500Mhz 128MB 10Gb CDROM 12.1'' OS X OFFICE 2004 Plus Upgraded Models AvailableThe Notebook1001 Faces of the Riddler / The Crime ComputerThe Computer Walks Among UsThe Ultimate Computer AffairLaptop Computer Cufflinks with Gift BoxComputer Charm14k Gold Overlay Brass Twist Link Chain BraceletHeart Shaped 24K Gold Overlay Leaf Pendant on Multi Chain NecklaceDesigner 24K Gold Overlay Leaf Pendant on Multi Chain Necklace

No comments:

Post a Comment