application program

program which is intended to perform a specific task

Application software is a subclass of computer software that employs the capabilities of a computer directly and thoroughly to a task that the user wishes to perform. This should be contrasted with system software which is involved in integrating a computer's various capabilities, but typically does not directly apply them in the performance of tasks that benefit the user. In this context the term application refers to both the application software and its implementation.
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<programming, operating system> (Or "application", "app") A complete, self-contained program that performs a specific function directly for the user. This is in contrast to system software such as the operating system kernel, server processes and libraries which exists to support application programs.
Editors for various kinds of documents, spreadsheets, and text formatters are common examples of applications. Network applications include clients such as those for FTP, electronic mail, telnet and WWW.
The term is used fairly loosely, for instance, some might say that a client and server together form a distributed application, others might argue that editors and compilers were not applications but tools for building applications.
One distinction between an application program and the operating system is that applications always run in "user mode" (or "non-privileged mode"), while operating systems and related utilities may run in "supervisor mode" (or "privileged mode").
The term may also be used to distinguish programs which communicate via a graphical user interface from those which are executed from the command line.
(1994-11-28)

Noun
1. a program that gives a computer instructions that provide the user with tools to accomplish a task; "he has tried several different word processing applications"
(synonym) application, applications programme
(hypernym) program, programme, computer program, computer programme
(hyponym) active application