Computer software determines the types of tasks a computer can help you accomplish. Some software helps you create documents; while other software helps you edit home videos, prepare your tax return or design the floor plan for a new house.
The instructions that tell a computer how to carry out a task are referred to as a computer program. These programs form the software that prepares a computer to do a specific task, such as document production, video editing, graphic design or Web browsing. In popular usage the term software refers to one or more computer programs and any additional files that are provided to carry out a specific type of task. Whether its on a CD or downloaded from the Web, todays software is typically composed of many files. You might be surprised by the number of files that are necessary to make software work. At least one of the files included in a software package contains an executable program designed to be launched, or started, by users. On PCs, these programs are stored in files that typically have.exe file extensions and are referred to as executable files. Other files supplied with a software package contain programs that are not designed to be run by users. These support programs contain instructions for the computer to use in conjunction with the main user-executable file. A support program can be activated by the main program as needed. Support programs often have file extensions such as.dll and.ocx.
In addition to program files, many software packages also include data files. As you might expect, these files contain any data that is necessary for a task, but not supplied by the user, such as Help documentation. The data files supplied with a software package sport files extensions such as.txt,.bmp, and.hlp. (see fig. 2):
The use of a main user-executable file plus several support programs and data files offers a great flexibility and efficiency for software developers. Support programs and data files from existing programs can usually be modified by developers for other programs without changing the main executable file. This modular approach can reduce the time required to create and test the main executable file, which usually contains a long and fairly complex program. This modular approach also allows software developers to reuse their support programs in multiple software products and adapt preprogrammed support modules for use in their own software. Modular programming techniques are of interest mainly to people who create computer programs; however these techniques affect the process of installing and uninstalling software. It is important, therefore, to remember that computer software consists of many files that contain user-executable programs, support programs, and data.
Software is categorized as application software or system software. The primary purpose of application software is to help people carry out tasks using a computer. In contrast, the primary purpose of system software your computers operating system, device drivers, programming languages, and utilities is to help the computer to carry out its basic operating functions.
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Computer software or just software is a general term used to describe the role that computer programs, procedures and documentation play in a computer system. The term includes:
Application software, such as word processors which perform productive tasks for users.
Firmware, which is software programmed resident to electrically programmable memory devices on board, mainboards or other types of integrated hardware carriers.
Middleware, which controls and co-ordinates distributed systems.
System software such as operating systems, which interface with hardware to provide the necessary services for application software.
Software testing is a domain dependent of development and programming.
Software testing consists of various methods to test and declare a software product fit before it can be launched for use by either an individual or a group.
Testware, which is an umbrella term or container term for all utilities and application software that serve in combination for testing a software package but not necessarily may optionally contribute to operational purposes.
As such, testware is not a standing configuration but merely a working environment for application software or subsets thereof.
Software includes things such as websites, programs or video games that are coded by programming languages like C or C++. "Software" is sometimes used in a broader context to mean anything which is not hardware but which is used with hardware, such as film, tapes and records.
Computer software is often regarded as anything but hardware, meaning that the "hard" are the parts that are tangible while the "soft" part is the intangible objects inside the computer. Software encompasses an extremely wide array of products and technologies developed using different techniques like programming languages, scripting languages, microcode, or an FPGA configuration.
The types of software include web pages developed by technologies like HTML, PHP, Perl, JSP, ASP.NET, XML, and desktop applications like Open Office, Microsoft Word developed by technologies like C, C++, Java, or C#.
Software usually runs on underlying software operating systems such as the Linux or Microsoft Windows. Software also includes video games and the logic systems of modern consumer devices such as automobiles, televisions, and toasters.
Computer software is so called to distinguish it from computer hardware, which encompasses the physical interconnections and devices required to store and execute (or run) the software. At the lowest level, software consists of a machine language specific to an individual processor. A machine language consists of groups of binary values signifying processor instructions that change the state of the computer from its preceding state. Software is an ordered sequence of instructions for changing the state of the computer hardware in a particular sequence. It is usually written in high-level programming languages that are easier and more efficient for humans to use (closer to natural language) than machine language. High-level languages are compiled or interpreted into machine language object code. Software may also be written in an assembly language, essentially, a mnemonic representation of a machine language using a natural language alphabet. Assembly language must be assembled into object code via an assembler.
The term "software" was first used in this sense by John W. Tukey in 1958. In computer science and software engineering, computer software is all computer programs. The theory that is the basis for most modern software was first proposed by Alan Turing in his 1935 essay Computable numbers with an application to the Entscheidungsproblem.
