A software or a application is a whole of programs, which allows a Ordinateur or a Computing system to ensure a task or a function in particular (example: software of Management of the client relationship, software of Production, software of Accounts Department, management software of the loans).

One distinguishes in general, in a Computing system, the material part (the Ordinateur and its peripheral S) and the software, immaterial part (the programs “written” on the Hard drive).

The software term is often employed to indicate a Computer program, and conversely, although a software can be made up of only one or a succession of programs.

This last case is all the more frequent as the reduced capacity of calculation of the Ordinateur obliges with a segmentation of the Tâche S in several separate modules; however, the enormous capacities of the current Micro-ordinateur S compared to the typical applications of the Bureautique allowed the realization of monolithic applications.

Generally, the programs are accompanied by a whole of Donnée S making it possible to make them function (for example, a play will come with many Image S, animations, sounds, etc).

To function, a software requires the use of a Ordinateur (Micro-ordinateur, station of calculation, Mainframe, Supercalculateur, etc) on which exists in the beginning a “software-engine” (Operating system) which accepts the “software-application”.

The whole needs an electric food .

Licenses

The right of use of the software is generally regulated by a license of use and the Royalty.

The big families of the most known licenses are:

  • licenses around the Free software ( free software in English ex: Project GNU);
  • the Gratuiciel ( freeware ex: icq.com);
  • the Partagiciel ( shareware ex: 6def.com);
  • of other types of licenses, such as the single-user or multipost licenses;
  • certain software finally is interns with companies and their diffusion is prohibited.

Various presentations of software

The programs can be various forms:

  • achievable: they can be carried out directly by the Ordinateur;
    • generally, they can be carried out only on one type of machine and particular operating system (example: Microsoft Windows on a PC compatible);
    • however, there exist achievable (in Bytecode the) achievable ones on a variety of platforms (like those of the language Java); they aim in fact the execution for a virtual Machine, which is itself a software available on the various platforms.

  • source files: it is generally about a text complying with the writing rules of a particular Computer programming language; as an indication, the order of magnitude of the size of a software as Microsoft Word is of a million lines of code;

    • for a compiled language: they must be translated into achievable by a Compilateur;
    • for a Interpreter: they are carried out directly with the reading (for example scripts Perl or).

  • libraries: it is about a whole of functions which, in themselves, are not achievable directly and do not offer functionality to the user, but provide services to other programs (for example, one will find libraries allowing a program to charge with animations or to play of the sounds); one finds in particular dynamic libraries ( DLL Windows or so GNU/Linux).

The Donnée S associated with the software can also be different Format S: traditional files, Databases (relational, hierarchical, etc). The data of the software can be burst in a great number of files, or all the software can be gathered in only one file; for example, under Windows, the definition of the User interface, the drawing of the icon S etc, are often integrated in the same file as the principal application.

Development of software

See also: Development of software

The software, according to their size, can be developed by a person alone, a small team, or a whole of coordinated teams. The development of great software by large teams poses major problems of coordination, because of the significant amount of information to be communicated between the speakers: documentation, meetings. For these reasons, the development of software in a professional context often follows strict rules allowing the group work and the maintenance of the code; indeed, often, the people who must operate later modifications in the code are not any more the people who developed it.

A new development model however tends to be spread: the bazaar (model used for the design of GNU/Linux)

A software in version béta (or béta-test) is a software not finalized, for which one carries out series of tests until a relative stability is reached. The people who seek the last faults of these versions of software are called béta-testers.

Bugs

See also: Bug (data-processing)

Errors of design in the software can cause incorrect behaviors, often called bugs. The gravity of those can go from very minor (p.ex., slightly incorrect appearance of an element of graphical interface), to catastrophic events (explosion of the rocket ARIANE flight 501, incorrect irradiation of patients by a processing machine…) while passing by more or less large losses of data, and, seldom, by a deterioration of the material.

It is difficult, for fundamental reasons, to produce software without bug; however, there exist mechanisms by which one can limit the quantity of bugs, even to remove them. Let us quote on the one hand precepts of organization of the teams of programming and their methodology, on the other hand tracking technologies of bugs in the software. Research in data processing developed a field of study, the formal checking, whose objective is to certify the quality of the software and to guarantee their reliability. As a whole, obtaining complex software little bugs is expensive as men and time. The more the anomalies are detected early with the length of the development of the software, the less their correction is expensive.

Opening of the source code

One classifies the software according to the availability of the Source code and the license which governs the distribution of the program:

  • open Code: everyone can read the source code. This term is not synonymous with Free software;

  • Code closed: the source code is available only for one minority of people;
  • Free software: everyone can study, copy, modify and distribute modified versions of the software (definition of the Free software foundation). The free software is protected for the majority by a license from use; For as much that does not mean that the software is free.
  • Software owner: at least one of these rights is not filled for the users. Most of the time, to acquire a license of use requires the payment of a certain sum to the creators of the software;
  • Software commercial: software intended for the sale, it can be free or owner.

Developers

See also: Amorce=Voir or to create the article, List of office automation software publishers

See also: List of the editors of video games

Critical software

See also: Profile of application

For the total safety of the information systems of an entity, it can be necessary to define Profils of application, in order to identify the Logiciels critics on which it is necessary to pay an special attention from the point of view of the safety.

See too

Simple: Software Zh-min-nan: Nńg-tea

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