Computer program

A computer program is a collection of instructions that performs a specific task when executed by a computer. A computer requires programs to function, and typically executes the program's instructions in a central processing unit.

A computer program is usually written by a computer programmer in a programming language. From the program in its human-readable form of source code, a compiler can derive machine code—a form consisting of instructions that the computer can directly execute. Alternatively, a computer program may be executed with the aid of an interpreter.

A part of a computer program that performs a well-defined task is known as an algorithm. A collection of computer programs, libraries and related data are referred to as software. Computer programs may be categorized along functional lines, such as application software or system software.

History

Early programmable machines

The earliest programmable machines preceded the invention of the digital computer. In 1801, Joseph-Marie Jacquard devised a loom that would weave a pattern by following a series of perforated cards. Patterns, including flowers and leaves, could be weaved and repeated by arranging the cards.

Program

Program (American spelling) or programme (British spelling) may refer to:

Communication

Business and management

Technology

Art and entertainment

Program management

Program management or programme management is the process of managing several related projects, often with the intention of improving an organization's performance. In practice and in its aims it is often closely related to systems engineering and industrial engineering.

The program manager has oversight of the purpose and status of the projects in a program and can use this oversight to support project-level activity to ensure the program goals are met by providing a decision-making capacity that cannot be achieved at project level or by providing the project manager with a program perspective when required, or as a sounding board for ideas and approaches to solving project issues that have program impacts. In a program there is a need to identify and manage cross-project dependencies and often the project management office (PMO) may not have sufficient insight of the risk, issues, requirements, design or solution to be able to usefully manage these. The program manager may be well placed to provide this insight by actively seeking out such information from the project managers although in large and/or complex projects, a specific role may be required. However this insight arises, the program manager needs this in order to be comfortable that the overall program goals are achievable.

Program (machine)

A program is a set of instructions used to control the behavior of a machine, often a computer (in this case it is known as a computer program).

Examples of programs include:

The execution of a program is a series of actions following the instructions it contains. Each instruction produces effects that alter the state of the machine according to its predefined meaning.

While some machines are called programmable, for example a programmable thermostat or a musical synthesizer, they are in fact just devices which allow their users to select among a fixed set of a variety of options, rather than being controlled by programs written in a language (be it textual, visual or otherwise).