With the proper software, a computer is a valuable tool. Software allows users to create letters, memos, reports, and other documents; develop multimedia presentations; design Web pages and diagrams; draw and alter images; record and enhance audio and video clips; prepare and file taxes; play single player or multiplayer games; compose e-mail messages and instant messages; and much more. To accomplish these and many other tasks, users work with application software.
Application software consists of programs designed to make users more productive and/or assist them with personal tasks. Application software has a variety of uses:
- To make business activities more efficient
- To assist with graphics and multimedia projects
- To support home, personal, and educational tasks
- To facilitate communications
Application software is available in a variety of forms: packaged, custom, Web application, open source, shareware, freeware, and public domain.
- Packaged software is mass-produced, copyrighted retail software that meets the needs of a wide variety of users, not just a single user or company. Packaged software is available in retail stores or on the Web.
- Custom software performs functions specific to a business or industry. Sometimes a company cannot find packaged software that meets its unique requirements. In this case, the company may use programmers to develop tailor-made custom software, which usually costs more than packaged software.
- A Web application is a Web site that allows users to access and interact with software from any computer or device that is connected to the Internet. Many Web sites provide free access to their programs; some charge a fee. Types of Web applications include e-mail, word processing, tax preparation, and game programs.
- Open source software is software provided for use, modification, and redistribution. This software has no restrictions from the copyright holder regarding modification of the software's internal instructions and its redistribution. Open source software usually can be downloaded from the Internet, often at no cost.
- Shareware is copyrighted software that is distributed at no cost for a trial period. To use a shareware program beyond that period, you send payment to the program developer. Shareware developers trust users to send payment if software use extends beyond the stated trial period. In some cases, a scaled-down version of the software is distributed free, and payment entitles the user to the fully functional product.
- Freeware is copyrighted software provided at no cost by an individual or a company that retains all rights to the software. Thus, programmers typically cannot incorporate freeware in applications they intend to sell. The word, free, in freeware indicates the software has no charge.
- Public-domain software has been donated for public use and has no copyright restrictions. Anyone can copy or distribute public-domain software to others at no cost.
Thousands of shareware, freeware, and public-domain programs are available on the Internet for users to download. Examples include communications, graphics, and game programs. These programs usually have fewer capabilities than packaged programs. Some packaged programs have trial versions, which you can use at no charge for a limited time, to see if the software meets your needs.
After you purchase or download software, you install it. During installation, the program may ask you to register and/or activate the software. Registering the software is optional and usually involves submitting your name and other personal information to the software manufacturer or developer. Registering the software often entitles you to product support. Product activation is a technique that some software manufacturers use to ensure the software is not installed on more computers than legally licensed. Usually, the software does not function or has limited functionality until you activate it via the Internet or telephone. Thus, activation is a required process for programs requesting it. You can activate some software more than once, for example, to run a program on both a desktop and notebook computer. Registering and/or activating the software also usually entitles you to free program updates for a specified time period, such as a year.
The Role of System Software
System software serves as the interface between the user, the application software, and the computer's hardware. To use application software, such as a word processing program, your computer must be running system software – specifically, an operating system. Three popular personal computer operating system are Windows, MacOS, and Linux.
Each time you start a computer, the operating system is loaded (copied) from the computer's hard disk into memory. Once the operating system is loaded, it coordinates all the activities of the computer. This includes starting application software and transferring data among input and output devices and memory. While the computer is running, the operating system remains in memory.
Utility Programs A utility program is a type of system software that assists users with controlling or maintaining the operation of a computer, its devices, or its software. Utility programs tipycally offer features that provide an environment conducive to successful use of application software. For example, utility programs protect a computer against malicious software and unauthorized intrusions, manage files and disks, compress files, play media files, and burn optical discs.
One of the more important utility programs protects a computer against malicious software, or malware, which is a program that acts without a user's knowledge and deliberately alters the computer's operations. A computer virus is a type of malicious software.
Working with Application Software
To use application software, you must instruct the operating system to start the program.
Personal computer operating systems often use the concept of a desktop to make the computer easier to use. The desktop is an on-screen work area that has a graphical user interface. An icon is a small image displayed on the screen that represents a program, a document, or some other object. A button is a graphical element that you activate to cause a specific action to occur. One way to activate a button is to click it. To click a button on the screen requires moving the pointer to the button and then pressing and releasing a button on the mouse (usually the left mouse button). The pointer is a small symbol displayed on the screen that moves as you interact with the mouse or other pointing device.
The Windows desktop contains a Start button on the lower-left corner of the taskbar. When you click the Start button, the Start menu is displayed on the desktop. A menu contains a list of commands from which you make selections. A command is an instruction that causes a program to perform a specific action.
To start a program, you can click its program name on a menu or in a list. This action instructs the operating system to start the program, which means the program's instructions load from a storage medium (such as a hard disk) into memory.
Once loaded into memory, the program appears in a window on the desktop. A window is a rectangular area of the screen that displays data and information. The top of a window has a title bar, which is a horizontal space that contains the window's name.
With the program loaded, you can create a new file or open an existing one. A file is a named collection of stored data, instructions, or information. A file can contain text, images, audio, and video. To distinguish among various files, each file has a file name. A file name is a unique combination of letters of the alphabet, numbers, and other characters that identifies a file. The title bar of the document window usually displays a document's file name.
In some cases, when you instruct a program to perform an activity such as print, the programs displays a dialog box. A dialog box is a window that provides information, presents available options, or requests a response.
