Softwares
Computer software, or simply software, is a part of a computer system that consists of data or computer instructions, in contrast to the physical hardware from which the system is built. In computer science and software engineering, computer software is all informationprocessed by computer systems, programs and data. Computer software includes computer programs, libraries and related non-executable data, such as online documentation or digital media. Computer hardware and software require each other and neither can be realistically used on its own.
At the lowest level, executable code consists of machine language instructions specific to an individual processor—typically a central processing unit (CPU). A machine language consists of groups of binary values signifying processor instructions that change the state of the computer from its preceding state. For example, an instruction may change the value stored in a particular storage location in the computer—an effect that is not directly observable to the user. An instruction may also (indirectly) cause something to appear on a display of the computer system—a state change which should be visible to the user. The processor carries out the instructions in the order they are provided, unless it is instructed to "jump" to a different instruction, or is interrupted (by now multi-core processors are dominant, where each core can run instructions in order; then, however, each application software runs only on one core by default, but some software has been made to run on many).
The majority of software is written in high-level programming languages that are easier and more efficient for programmers to use because they are closer than machine languages to natural languages.[1] High-level languages are translated into machine language using a compiler or an interpreter or a combination of the two. Software may also be written in a low-level assembly language, which has strong correspondence to the computer's machine language instructions and is translated into machine language using an assembler.
Types
On virtually all computer platforms, software can be grouped into a few broad categories.
Purpose, or domain of use
| Part of a series on |
| E-commerce |
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| Online goods and services |
| Retail services |
| Marketplace services |
| Mobile commerce |
| Customer service |
| E-procurement |
| Purchase-to-pay |
Based on the goal, computer software can be divided into:
- Application software
is software that uses the computer system to perform special functions or provide entertainment functionswhich beyond the basic operation of the computer itself. There are many different types of application software, because the range of tasks that can be performed with a modern computer is so large—see list of software. - System software
is software that directly operates the computer hardware, to provide basic functionality needed by users and other software, and to provide a platform for running application software.[2] System software includes:which - Operating systems
arewhich collections of software that manage resources and provides common services for other software that runs "on top" of them. Supervisory programs, boot loaders, shells and window systems are core parts of operating systems. In practice, an operating system comes bundled with additional software (including application software) so that a user can potentially do some work with a computer that only has one operating system.essential - Device drivers
operate or control a particular type of device that is attached to a computer. Each device needs at least one corresponding device driver; because a computer typically has at minimum at least one input device and at least one output device, a computer typically needs more than one device driver.which - Utilities
are computer programs designed to assist users in the maintenance and care of their computers.which
- Operating systems
- Malicious software or malware
is software that is developed to harm and disrupt computers. As such, malware is undesirable. Malware is closely associated with computer-related crimes, though some malicious programs may have been designed as practical jokes.which
Nature or domain of execution
- Desktop applications such as web browsers and Microsoft Office, as well as smartphone and tablet applications (called "apps"). (There is a push in some parts of the software industry to merge desktop applications with mobile apps, to some extent. Windows 8, and later Ubuntu Touch, tried to allow the same style of application user interface to be used on desktops, laptops and mobiles.)
- JavaScript scripts are pieces of software traditionally embedded in web pages that are run directly inside the web browser when a web page is loaded without the need for a web browser plugin. Software written in other programming languages
within the web browser if the software is either translated into JavaScript, or if a web browser plugin that supports that language is installed; the most common example of the latter is ActionScript scripts, which are supported by the Adobe Flash plugin.can also be run - Server software, including:
- Web applications, which usually run on the web server and output dynamically generated web pages to web browsers, using e.g. PHP, Java, ASP.NET, or even JavaScript that runs on the server. In modern times these commonly include some JavaScript to be run in the web browser as well, in which case they typically run partly on the server, partly in the web browser.
- Plugins and extensions are software that extends or modifies the functionality of another piece of software, and require that
be used in order to function;software - Embedded software resides as firmware within embedded systems, devices dedicated to a single use or a few
as cars and televisions (although some embedded devices such as wirelessuses such can themselves be part of an ordinary, non-embedded computer system such as a PC or smartphone).[3] In the embedded systemchipsets is sometimes no clear distinction between the system software and the application software. However, some embedded systems run embedded operating systems, and these systems do retain the distinction between system software and application software (although typically there will only be one, fixed, application which is always run).context there - Microcode is a special, relatively obscure type of embedded software which tells the processor itself how to execute machine code, so it is actually a lower level than machine code. It is typically proprietary to the processor manufacturer, and any necessary correctional microcode software updates are supplied by them to users (which is much cheaper than shipping replacement processor hardware). Thus an ordinary programmer would not expect to ever have to deal with it.
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