Computer software

Computer software or just software is a general term used to describe a collection of computer programs, procedures and documentation that perform some tasks on a computer system. It plays an important role in computer-based information systems because hardware would be useless without it. Software comprises the instructions that tell the hardware what to do. This term includes application software such as word processors which perform productive tasks for users, system software such as operating systems, which interface with hardware to provide the necessary services for application software, and middleware which controls and co-ordinates distributed systems.
Applications software is a collection of related programs designed to perform a specific task—to solve a particular problem for the user. Typical applications include: industrial automation, business software, educational software, medical software, databases, and computer games. Businesses are probably the biggest users of application software, but almost every field of human activity now uses some form of application software.
Systems software starts up (boots) the computer and functions as the principal coordinator of all the hardware components and applications software programs. It includes: operating systems, device drivers, diagnostic tools, servers, windowing systems, utilities and more. The purpose of systems software is to insulate the applications programmer as much as possible from the details of the particular computer complex being used, especially memory and other hardware features, and such as accessory devices as communications, printers, readers, displays, keyboards, etc.
Middleware controls and co-ordinates distributed systems. The software consists of a set of enabling services that allow multiple processes running on one or more machines to interact across a network
The six major categories of applications software are general business management, industry-specific, special disciplines, education, personal/home management, and general- purpose for the user.
Software includes websites, programs, video games etc. that are coded by programming languages like C, C++, etc.
Computer software encompasses an extremely wide array of products and technologies developed using different techniques like programming languages, scripting languages etc. Software usually runs on a software platform which can either be provided by the operating System or by OS independent platforms like Java and .NET. Software written for one platform is usually unable to run on other platforms so that for instance, Microsoft Windows software will not be able to run on Mac OS because of the differences relating to the platforms and their own standards. These applications can work using software porting, interpreters or re-writing the source code for that platform.
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 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.