Front-end and back-end are generalized terms that refer to the initial and the end stages of a process. The front-end is responsible for collecting input in various forms from the user and processing it to conform to a specification the back-end can use. The front-end is a kind of interface between the user and the back-end.

Contents 1 Computer science 2 Technology 3 Business 4 Sports 5 See also 6 References

[edit] Computer science

In software architecture there are many layers between the hardware and end-user. Each can be spoken of as having a front- and back-end. The "front" is an abstraction, simplifying the underlying component by providing a user-friendly interface.

In software design, the Model-view-controller for example, provides front- and back-ends for the database, the user, and the data processing components. The separation of software systems into "front-ends" and "back-ends" simplifies development and separates maintenance.

For major computer subsystems, a graphical file manager is a front-end to the computer's file system, and a shell interfaces the operating system — the front-end faces the user and the back-end launches the programs of the operating system in response.

Using the CLI ( command-line interface ) feature requires the acquisition of special terminology and the memorization of the commands, and so a GUI ( graphical user interface ) acts as a front-end desktop environment instead. In the Unix environment, ncurses is a simpler, semi-graphical front-end to the CLI. At the level of the Unix CLI itself, most commands are filters — standalone commands that can also serve as front-end and back-end to other commands. (They function by piping data between themselves, mostly for text processing. For example: CLI-prompt> cmd1 | cmd2 | cmd3 | cmd4 )

In network computing "front-end" can refer to any hardware that optimizes or protects network traffic. It is called application front-end hardware because it is placed on the network's out-facing front-end or boundary. Network traffic passes through the "application's front-end hardware" before entering the network.

In compilers, the front-end translates a computer programming source language into an intermediate representation, and the back-end works with the internal representation to produce code in a computer output language. The back-end usually optimizes to produce code that runs faster. The front-end/back-end distinction can separate the parser section that deals with source code and the back-end that does code generation and optimization; some designs (such as GCC) offer the choice between multiple front-ends (parsing different source languages) and/or multiple back-ends (generating code for different target processors).

In speech synthesis, the front-end refers to the part of the synthesis system that converts the input text into a symbolic phonetic representation, and the back-end converts the symbolic phonetic representation into actual sounds.

In the context of WWW applications, a mediator is a service that functions simultaneously as a server on its front end and as a client on its back end.^[1]

[edit] Technology

In radio receivers, the 'front-end' consists of the package containing the feed horn and wave guide, as well as the antennas required to detect the radio signal. The 'back-end' refers to the amplification and filtering systems that refine and edit the signal before presenting it to the user.

In electronic design automation, front-end stages of the design cycle are logical and electrical design (e.g., schematic capture, logic synthesis). Sometimes floor planning is also considered front-end. Back-end are place and route, custom layout design and physical verification (design rule checking, layout versus schematic, parasitics extraction).

The semiconductor industry is divided into front-end (wafer fabrication) and back-end (product assembly, packaging and testing) operations.

[edit] Business

Front-end and back-end have several meanings in financial situations. For instance, transactions to purchase mutual funds can have a front-end sales load that investors pay when they purchase fund shares and/or a back-end or deferred sales load investors pay when they redeem their shares.^[2]

Other uses of these terms in business include:

• A "back-end plan" is a type of poison pill arrangement. In this plan, current shareholders of the targeted company receive a rights dividend, which allows for exchange of a share of stock (including voting rights) for senior securities or cash equivalent to the "back-end" price established by the targeted firm. As a result of this strategy, the takeover bidder is unable to both 1) exercise this right, and 2) easily deter the rise in acquisition price.

• Front-end refers to the early stages of product development (i.e. opportunity identification and exploration). Commonly the modifier "fuzzy" is also used, addressing the difficulties of managing and planning this process.

• The process of handling stock is often broken down into three stages: in the "front office" orders are taken from the customers, passed on to the "middle office" for actual processing, and finally to the "back office" which handles accounting and billing. This terminology is used in a number of seemingly unrelated industries; in stock trading, for instance, the front office is an order placed by a user or broker in very general terms, the middle office handles the actual trading within those terms, and then they inform the back office of the actual details of the transaction.

• In television production, the "front-end" refers to an order for a series that is for a duration less than the full length of the season. For instance, a network may order only 13 episodes as a hedge in case the program is not popular enough to last the entire season. If the ratings are satisfactory, the "back-end" can then be ordered (typically, another nine episodes).

• In television and movie production, the "back-end" can refer to an agreement by which a performer or producer is paid (at least in part) based on profit sharing instead of upfront payments. These profits are usually realized well after the main part of the production has ended.

[edit] Sports

In curling, the first two members of the team's delivery rotation, called the "lead" and "second," are together referred to as the "front-end" of the team. The latter two members in the delivery rotation, called the "third" (or "vice," "mate") and "skip" are together referred to as the "back-end."

[edit] See also

• Back-end database
• Client-server architecture
• Software architecture
• Three-tier system

[edit] References