What is computer software

Software

Sometimes abbreviated as SW and S/W, software is a collection of instructions that enable the user to interact with a computer, its hardware, or perform tasks. Without software, most computers would be useless. For example, without your Internet browser software, you could not surf the Internet or read this page. Without an operating system, the browser could not run on your computer. The picture shows a Microsoft Excel box, an example of a spreadsheet software program.

Examples and types of software

Below is a list of the different kinds of software a computer may have installed with examples of related programs. Click any of the links below for additional information.

Although application software is thought of as a program, it can be anything that runs on a computer. The following table also has a «Program?» column to clarify any software that’s not a program.

See our program definition for additional examples of computer programs.

How do you get software?

Software can be purchased at a retail computer store or online and come in a box containing all the disks (floppy diskette, CD, DVD, or Blu-ray), manuals, warranty, and other documentation.

Software can also be downloaded to a computer over the Internet. Once downloaded, setup files are run to start the installation process on your computer.

Free software

There are also a lot of free software programs available that are separated into the following categories.

Retail software that is copied but not purchased or does not have a software license is known as software piracy and is illegal.

See our top 10 free PC programs everyone should have, for a list of software you may want to install on your computer first.

Installing and uninstalling software

How do you use computer software?

Once the software is installed on the computer hard drive, the program can be used at any time. On a Windows computer, a program icon is added to the Start menu or Start screen, depending on your version of Windows.

How to maintain software

After the software is installed on your computer, it may need to be updated to fix any found errors. Updating a program can be done using software patches. Once updates are installed, any problems that may have been experienced in the program will no longer occur.

How is software created and how does it work?

A computer programmer (or several computer programmers) write the instructions using a programming language, defining how the software should operate on structured data. The program may then be interpreted, or compiled into machine code.

When I save a document, is that file also considered software?

When you create or edit a file using software — a Microsoft Word document, for instance, or a Photoshop image — that file is considered a software «resource» or «asset.» However, the file itself is not considered «software» even though it is an essential part of what your software is doing.

What was the first piece of computer software?

The first software program that was held in electronic memory was credited to and written by Tom Kilburn. The program calculated the highest factor of the integer 2 18 = 262,144, and was successfully executed on June 21, 1948, at the University of Manchester, England. The computer that held that program was called the SSEM (Small Scale Experimental Machine), otherwise known as the «Manchester Baby.» This event is widely celebrated as the birth of software.

How expensive is software?

What is Computer Software?

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Computer software is a program that tells a computer what to do. These instructions might be internal commands, such as updating the system clock, or a response to external input received from the keyboard or mouse. Though there are many different types of software made both with open source and proprietary standards, the programming mostly comes down to a few basic rules.

Games are one type of computer software.

Hardware vs. Software

The fundamental difference between hardware and software is that the first is tangible while the second is not. Hardware is the machine itself and does all of the physical work, while software tells the various hardware components what to do and how to interact with each other. This makes it possible for computers to adapt to new tasks or to install new hardware. While hardware includes things like monitors, Central Processing Units (CPUs), keyboards, and mice; software includes things like word processing programs, operating systems, and games.

Types

There are two main types of computer software: system and application. The first type is used just to run the hardware, while the second is used to do other things. The main types of system software are operating systems, like Windows™ OS X, or Linux; and drivers, which are programs that allow a computer to interact with other devices, like printers and video cards. There are many different types of application software, including games, media players, word processors, anti-virus programs, and applications for making new programs.

Programmers create either open source or proprietary computer software.

Computer software is often tested by hackers for vulnerabilities before being released to the public.

How It Works

Hardware only understands the two basic concepts, on and off, which are represented as 1s and 0s in binary language. Software acts as the translator between human languages and binary, which makes it possible for the hardware to understand the instructions being fed into it. Programmers write commands called source code in programming languages that are similar to what someone might use in everyday speech. Another program called a compiler is then used to transform the source code commands into binary. The result is an executable computer program.

Open Source vs. Proprietary

Programmers create either open source or proprietary computer software. The first type can be edited and adapted by users, while the second is protected and not intended to be edited by people outside the company that sells it. While open source programs are usually free, proprietary ones are licensed to distributors and must be paid for.

Both types generally have a comparable quality of programming, but fixes for bugs generally come faster for open source products than for proprietary ones. Also, some people prefer to use open source applications because they can feel a sense of ownership in the end project or feel that computer software companies create monopolies and want alternatives. Others prefer closed source programs because they are sometimes more stable or be less vulnerable to hackers, often come in suites, and come with customer service from the company.

Some IT professionals specialize in hardware, while others focus on programming software.

Computer software

Computer software is a program that enables a computer to perform a specific task, as opposed to the physical components of the system (hardware). This includes application software such as a word processor, which enables a user to perform a task, and system software such as an operating system, which enables other software to run properly, by interfacing with hardware and with other software.

Contents

The term «software» was first used in this sense by John W. Tukey in 1957. In computer science and software engineering, computer software is all computer programs. The concept of reading different sequences of instructions into the memory of a device to control computations was invented by Charles Babbage as part of his difference engine. 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. [1]

Relationship to hardware

Computer software is so called in contrast to computer hardware, which encompasses the physical interconnections and devices required to store and execute (or run) the software. In computers, software is loaded into random access memory (RAM) and executed in the central processing unit. At the lowest level, software consists of a machine language specific to an individual processor. The machine language consists of groups of binary values signifying processor instructions (object code), which 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.

Relationship to data

Software has historically been considered an intermediary between electronic hardware and data, which are defined by the instructions defined by the software. As computational math becomes increasingly complex, the distinction between software and data becomes less precise. Data has generally been considered as either the output or input of executed software. However, data is not the only possible output or input. For example, (system) configuration information may also be considered input, although not necessarily considered data (and certainly not applications data). The output of a particular piece of executed software may be the input for another executed piece of software. Therefore, software may be considered an interface between hardware, data, and/or (other) software.

Types

Practical computer systems divide software into three major classes: System software, programming software, and application software, although the distinction is arbitrary and often blurred.

Computer viruses

Computer viruses are a malignant type of computer program even though they might not be considered software. They can be created as any of the three types of software. Some viruses cause minor problems, such as slowing down a computer or using email to spread. Other viruses can cause more serious problems, such as destroying data or damaging hardware.

Program and library

A program may not be sufficiently complete for execution by a computer. In particular, it may require additional software from a software library to be complete. Such a library may include software components used by stand-alone programs, but which cannot be executed on their own. Thus, programs may include standard routines that are common to many programs, extracted from these libraries. Libraries may also include stand-alone programs that are activated by some computer event and/or perform some function (such as computer «housekeeping») but do not return data to their activating program. Programs may be called by other programs and/or may call other programs.

Three layers

Users often see things differently than programmers. People who use modern general purpose computers (as opposed to embedded systems, analog computers, supercomputers, and so forth) usually see three layers of software performing a variety of tasks: Platform, application, and user software.

Operation

Computer software has to be «loaded» into the computer’s storage (also known as memory and RAM).

Once the software is loaded, the computer is able to execute the software. Computers operate by executing the computer program. This involves passing instructions from the application software, through the system software, to the hardware which ultimately receives the instruction as machine code. Each instruction causes the computer to carry out an operation—moving data, carrying out a computation, or altering the control flow of instructions.

Data movement is typically from one place in memory to another. Sometimes it involves moving data between memory and registers which enable high-speed data access in the CPU.

A simple example of the way software operates is what happens when a user selects an entry such as «Copy» from a menu. In this case, a conditional instruction is executed to copy text from data in a «document» area residing in memory, perhaps to an intermediate storage area known as a «clipboard» data area. If a different menu entry such as «Paste» is chosen, the software may execute the instructions to copy the text from the clipboard data area to a specific location in the same or another document in memory.

Currently, almost the only limitations on the use of computer software in applications is the ingenuity of the designer/programmer. Consequently, large areas of activities (such as playing grand master level chess) formerly assumed to be impossible if done by software simulation are now routinely programmed. The only area that has so far proved reasonably secure from software simulation is the realm of human art—especially, pleasing music and literature.

Quality and reliability

Software reliability considers the errors, faults, and failures related to the creation and operation of software. A lot of the quality and reliability of a program has to do with the Application software being written for a specific System software. One example is that an application for an older System software may not work on a newer one.

Software architecture

The software architecture of a system comprises its software components, their external properties, and their relationships with one another. The term also refers to documentation of a system’s software architecture. [2]

History

The origins of software architecture as a concept were first identified in the research work of Edsger Dijkstra in 1968, and David Parnas in the early 1970s. The scientists emphasized that the structure of a software system matters and getting the structure right is critical. [3] The study of the field increased in popularity since the early 1990s, with research work concentrating on architectural styles (patterns), architecture description languages, architecture documentation, and formal methods. [4]

Mary Shaw and David Garlan of Carnegie Mellon wrote a book titled, Software Architecture: Perspectives on an Emerging Discipline in 1996, which brought forward the concepts in Software Architecture, such as components, connectors, styles, and so on. UCI’s Institute for Software Research’s efforts in software architecture research is directed primarily in architectural styles, architecture description languages, and dynamic architectures.

Describing architectures

Architecture description languages

Architecture Description Languages (ADLs) are used to describe a Software Architecture. Several different ADLs have been developed by different organizations, including Wright (developed by Carnegie Mellon), Acme (developed by Carnegie Mellon), xADL (developed by UCI), Darwin (developed by Imperial College London), and DAOP-ADL (developed by University of Málaga). Common elements of an ADL are component, connector and configuration.

Views

Software architecture is commonly organized in views, [5] which are analogous to the different types of blueprints made in building architecture.

License

Software license gives the user the right to use the software in the licensed environment, some software comes with the license when purchased off the shelf, or OEM license when bundled with hardware. Software can also be in the form of freeware or shareware.

Proprietary software

Proprietary software is software that has restrictions on using and copying it, usually enforced by a proprietor. The prevention of use, copying, or modification can be achieved by legal or technical means. Technical means include releasing machine-readable binaries only, and withholding the human-readable source code. Legal means can involve software licensing, copyright, and patent law. Proprietary software can be sold for money as commercial software or available at zero-price as freeware. The monopoly provided by proprietary software allows a distributor of commercial copies to charge any price for those copies. Distributors of proprietary software have more control over what users can do with the software than nonproprietary software.

Free software

Free software, as defined by the Free Software Foundation, is software which can be used, copied, studied, modified, and redistributed without restriction. Freedom from such restrictions is central to the concept, with the opposite of free software being proprietary software (a distinction unrelated to whether a fee is charged). The usual way for software to be distributed as free software is for the software to be licensed to the recipient with a free software license (or be in the public domain), and the source code of the software to be made available (for a compiled language). Most free software is distributed online without charge, or off-line at the marginal cost of distribution, but this is not required, and people may sell copies for any price.

To help distinguish libre (freedom) software from gratis (zero price) software, Richard Stallman, founder of the free software movement, developed the following explanation: «Free software is a matter of liberty, not price. To understand the concept, you should think of ‘free’ as in ‘free speech’, not as in ‘free beer.'» More specifically, free software means that computer users have the freedom to cooperate with whom they choose, and to control the software they use.

Open-source software

Open-source software is computer software whose source code is available under a copyright license that permits users to study, change, and improve the software, and to redistribute it in modified or unmodified form. It is the most prominent example of open source development.

In 1998, a group of individuals advocated that the term «free software» be replaced by open-source software (OSS) as an expression which is less ambiguous and more comfortable for the corporate world. Software developers may want to publish their software with an open-source software license, so that anybody may also develop the same software or understand how it works. Open-source software generally allows anybody to make a new version of the software, port it to new operating systems and processor architectures, share it with others or market it. The aim of open source is to let the product be more understandable, modifiable, duplicable, reliable, or simply accessible, while it is still marketable.

The Open Source Definition, notably, presents an open-source philosophy, and further defines a boundary on the usage, modification and redistribution of open-source software. Software licenses grant rights to users which would otherwise be prohibited by copyright. These include rights on usage, modification and redistribution. Several open-source software licenses have qualified within the boundary of the Open Source Definition. The most prominent example is the popular GNU General Public License (GPL). While open source presents a way to broadly make the sources of a product publicly accessible, the open-source licenses allow the authors to fine tune such access.

Freeware

Freeware is copyrighted computer software which is made available for use free of charge, for an unlimited time, as opposed to shareware, in which the user is required to pay (for example, after some trial period). The only criterion for being classified as «freeware» is that the software must be made available for use for an unlimited time at no cost. The software license may impose one or more other restrictions on the type of use including personal use, individual use, non-profit use, non-commercial use, academic use, commercial use. or any combination of these. For instance, the license may be «free for personal, non-commercial use.» There is some software that may be considered freeware, but that have limited distribution; that is, they may only be downloaded from a specific site, and they can not be redistributed. Hence, such software wouldn’t be freely redistributable software. According to the basic definition, that software would be freeware; according to stricter definitions, they wouldn’t be. Everything created with the freeware programs can be distributed at no cost (for example graphic, documents, waves made by user).

Freeware contrasts with free software, because of the different meanings of the word «free.» Freeware is gratis and refers to zero price, versus free software that is described as «libre,» which means free to study, change, copy, redistribute, share, and use the software in any purpose. However, many programs are both freeware and free software. They are available for zero price, provide the source code and are distributed with free software permissions. This software would exclusively be called free software to avoid confusion with freeware that usually does not come with the source code and is therefore proprietary software.

Shareware

Shareware is a marketing method for commercial software, whereby a trial version is distributed in advance and without payment, as is common for proprietary software. Shareware software is typically obtained free of charge, either by downloading from the Internet or on magazine cover-disks. A user tries out the program, and thus shareware has also been known as «try before you buy,» demoware, trialware, and by many other names. A shareware program is accompanied by a request for payment, and the software’s distribution license often requires such a payment. Payment is often required once a set period of time has elapsed after installation.

Notes

References

External links

All links retrieved March 17, 2017.

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What Is Software?

Learn more about what software is and what it can do

Software, in broad terms, is a set of instructions (generally referred to as «code») that’s positioned between you and the device’s hardware, enabling you to use it.

What Is Computer Software?

But what is computer software, really? It’s an invisible component of a computer system that makes it possible for you to interact with the computer’s physical components. Software allows you to communicate with smartphones, tablets, game boxes, media players, and similar devices.

It’s important to note that there’s a distinct difference between hardware and software. Software is an intangible resource. You can’t hold it in your hands. Hardware consists of tangible resources such as mice, keyboards, USB ports, CPUs, memory, and printers. Phones are hardware. iPads, Kindles, and Fire TV sticks are hardware. Hardware and software work together to make a system functional.

Types of Software

While all software is software, your day-to-day use of software likely comes in two ways: one is the system software, and the other is as an application.

The Windows operating system is an example of system software and comes preinstalled on Windows computers. It’s what lets you interact with the physical computer system. Without this software, you couldn’t turn on your computer, get into Windows, and access the Desktop. All smart devices have system software, including iPhone and Android devices. Again, this type of software is what runs the device and enables you to use it.

Application software is the second type and is more about the user than the system. Application software is what you use to do work, access media, or play games. It’s often preinstalled with the operating system by computer manufacturers and may include music players, office suites, and photo editing apps. Users can also install compatible third-party software.

Examples of application software include Microsoft Word, Adobe Reader, Google Chrome, Netflix, and Spotify. There’s anti-virus software too, at least for computer systems. Finally, apps are software. Windows 8 and 10 support apps, as do all smartphones and tablets.

Stand-Alone Software

Many types of software are considered stand-alone software, meaning that the software is not part of a bundle and can run separately from other programs on your device. Some stand-alone software runs on its own using a flash or disk drive; other types don’t require internet connections and rely on the manufacturer’s disks instead. Some software, however, is dependent upon an operating system or needs access to other programs on the device to run correctly.

Who Creates Software?

The definition of software implies that someone must sit at a computer somewhere and write the computer code for it. It’s true; there are independent coding experts, teams of engineers, and large corporations creating software and vying for your attention.

Adobe makes Adobe Reader and Adobe Photoshop; Microsoft makes the Microsoft Office Suite; McAfee makes anti-virus software; Mozilla makes Firefox; Apple makes iOS. Third parties make apps for Windows, iOS, Android, and more. People are writing software all over the world right now.

How to Get Software

Operating systems come with some software already installed. In Windows 10, there’s the Microsoft Edge web browser, for instance, and applications like WordPad and Fresh Paint. In iOS, there are Photos, Weather, Calendar, and Clock apps (software). If your device doesn’t have all of the software you need, you can add more.

One way a lot of people add software is by downloading it from specific stores. On the iPhone, for example, people download apps from the App Store, and on the Android, people download apps from Google Play. Apps are software, perhaps with a friendlier name.

Another way people add software to their computers is via physical media such as a DVD.

software

Software is a set of instructions, data or programs used to operate computers and execute specific tasks. It is the opposite of hardware, which describes the physical aspects of a computer. Software is a generic term used to refer to applications, scripts and programs that run on a device. It can be thought of as the variable part of a computer, while hardware is the invariable part.

The two main categories of software are application software and system software. An application is software that fulfills a specific need or performs tasks. System software is designed to run a computer’s hardware and provides a platform for applications to run on top of.

Other types of software include programming software, which provides the programming tools software developers need; middleware, which sits between system software and applications; and driver software, which operates computer devices and peripherals.

Early software was written for specific computers and sold with the hardware it ran on. In the 1980s, software began to be sold on floppy disks, and later on CDs and DVDs. Today, most software is purchased and directly downloaded over the internet. Software can be found on vendor websites or application service provider websites.

Among the various categories of software, the most common types include the following:

Application software

Application software consists of many programs that perform specific functions for end users, such as writing reports and navigating websites. Applications can also perform tasks for other applications. Applications on a computer cannot run on their own; they require a computer’s OS, along with other supporting system software programs, to work.

These desktop applications are installed on a user’s computer and use the computer memory to carry out tasks. They take up space on the computer’s hard drive and do not need an internet connection to work. However, desktop applications must adhere to the requirements of the hardware devices they run on.

Web applications, on the other hand, only require internet access to work; they do not rely on the hardware and system software to run. Consequently, users can launch web applications from devices that have a web browser. Since the components responsible for the application functionality are on the server, users can launch the app from Windows, Mac, Linux or any other OS.

System software

System software sits between the computer hardware and the application software. Users do not interact directly with system software as it runs in the background, handling the basic functions of the computer. This software coordinates a system’s hardware and software so users can run high-level application software to perform specific actions. System software executes when a computer system boots up and continues running as long as the system is on.

Here are the key differences between system and application software.

The software development lifecycle is a framework that project managers use to describe the stages and tasks associated with designing software. The first steps in the design lifecycle are planning the effort and then analyzing the needs of the individuals who will use the software and creating detailed requirements. After the initial requirements analysis, the design phase aims to specify how to fulfill those user requirements.

The next is step is implementation, where development work is completed, and then software testing happens. The maintenance phase involves any tasks required to keep the system running.

The software design includes a description of the structure of the software that will be implemented, data models, interfaces between system components and potentially the algorithms the software engineer will use.

The software design process transforms user requirements into a form that computer programmers can use to do the software coding and implementation. The software engineers develop the software design iteratively, adding detail and correcting the design as they develop it.

The different types of software design include the following:

Software quality measures if the software meets both its functional and nonfunctional requirements.

Functional requirements identify what the software should do. They include technical details, data manipulation and processing, calculations or any other specific function that specifies what an application aims to accomplish.

Software testing detects and solves technical issues in the software source code and assesses the overall usability, performance, security and compatibility of the product to ensure it meets its requirements.

The dimensions of software quality include the following characteristics:

To maintain software quality once it is deployed, developers must constantly adapt it to meet new customer requirements and handle problems customers identify. This includes improving functionality, fixing bugs and adjusting software code to prevent issues. How long a product lasts on the market depends on developers’ ability to keep up with these maintenance requirements.

When it comes to performing maintenance, there are four types of changes developers can make, including:

Modern software development

DevOps is an organizational approach that brings together software development and IT operations teams. It promotes communication and collaboration between these two groups. The term also describes the use of iterative software development practices that use automation and programmable infrastructure. Get the full picture in our ultimate guide to DevOps.

A software license is a legally binding document that restricts the use and distribution of software.

Typically, software licenses provide users with the right to one or more copies of the software without violating copyright. The license outlines the responsibilities of the parties that enter into the agreement and may place restrictions on how the software can be used.

Software licensing terms and conditions generally include fair use of the software, the limitations of liability, warranties, disclaimers and protections if the software or its use infringes on the intellectual property rights of others.

Licenses typically are for proprietary software, which remains the property of the organization, group or individual that created it; or for free software, where users can run, study, change and distribute the software. Open source is a type of software where the software is developed collaboratively, and the source code is freely available. With open source software licenses, users can run, copy, share and change the software similar to free software.

Over the last two decades, software vendors have moved away from selling software licenses on a one-time basis to a software-as-a-service subscription model. Software vendors host the software in the cloud and make it available to customers, who pay a subscription fee and access the software over the internet.

Although copyright can prevent others from copying a developer’s code, a copyright cannot stop them from developing the same software independently without copying. A patent, on the other hand, enables a developer to prevent another person from using the functional aspects of the software a developer claims in a patent, even if that other person developed the software independently.

In general, the more technical software is, the more likely it can be patented. For example, a software product could be granted a patent if it creates a new kind of database structure or enhances the overall performance and function of a computer.

The following is a brief timeline of the history of software: