For the use of JavaScript on Wikipedia, see Wikipedia:JavaScript.

JavaScript is a scripting language most often used for client-side web development. A programming paradigm is a fundamental style of Computer programming. A multi-paradigm programming language is a Programming language that supports more than one Programming paradigm. Prototype-based programming is a style of Object-oriented programming in which classes are not present and behavior reuse (known as inheritance in class-based In Computer science, functional programming is a Programming paradigm that treats Computation as the evaluation of mathematical functions and In Computer science, imperative programming is a Programming paradigm that describes computation in terms of statements that change a program state "Scripting" redirects here For other uses see Script. Year 1995 ( MCMXCV) was a Common year starting on Sunday. Events of 1995 Brendan Eich (born 1961 is a Computer programmer and creator of the JavaScript Programming language. A software developer is a person or organization concerned with facets of the software development process wider than design and coding a somewhat broader scope of Netscape Communications (formerly known as Netscape Communications Corporation and commonly known as Netscape) is an American computer services company The Mozilla Foundation is a Non-profit organization that exists to support and provide leadership for the Open source Mozilla project In Computer science, a type system defines how a Programming language classifies values and expressions into '''types''', how it can In Computer science, a type system defines how a Programming language classifies values and expressions into '''types''', how it can In Computer science, weak typing (aka loose typing) is a property attributed to the Type systems of some Programming languages It is the opposite In Computer programming, duck typing is a style of Dynamic typing in which an object's current set of methods and properties determines the valid Implementation is the realization of an application or execution of a Plan, idea Model, Design, Specification, standard, Algorithm Rhino is an Open source JavaScript engine. It is developed entirely in Java and managed by the Mozilla Foundation. KJS is KDE 's ECMAScript / JavaScript engine that was originally developed for the KDE project's Konqueror web browser by Harri WebKit is an Open source Application framework that provides a foundation upon which to build a Web browser. JScript is the Microsoft dialect of the ECMAScript Scripting language specification JScript.NET is a.NET Programming language developed by Microsoft as a natural successor to Microsoft's Active Scripting language JScript Self is an object-oriented programming language based on the concept of prototypes. tags please moot on the talk page first! --> In Computing, C is a general-purpose cross-platform block structured Scheme is a Multi-paradigm programming language. It is one of the two main dialects of Lisp and supports a number of programming paradigms but is NOTES FOR EDITORS "Perl" is not an acronym (read the "Name" section below Python is a general-purpose High-level programming language. Its design philosophy emphasizes programmer productivity and code readability "Scripting" redirects here For other uses see Script. In Computer networking the term client-side refers to operations that are performed by the client in a Client-server relationship It was the originating dialect of the ECMAScript standard. ECMAScript is a Scripting language, standardized by Ecma International in the ECMA-262 specification. It is a dynamic, weakly typed, prototype-based language with first-class functions. This article is about a class of programming languages for the method for reducing the runtime of algorithms see Dynamic programming. In Computer science, weak typing (aka loose typing) is a property attributed to the Type systems of some Programming languages It is the opposite Prototype-based programming is a style of Object-oriented programming in which classes are not present and behavior reuse (known as inheritance in class-based In Computer science, a Programming language is said to support first-class functions (or function literal) if it treats functions as JavaScript was influenced by many languages and was designed to look like Java, but be easier for non-programmers to work with. ^[1][2]

Although best known for its use in websites (as client-side JavaScript), JavaScript is also used to enable scripting access to objects embedded in other applications (see below). A website (alternatively web site or Web site, a back-construction from the Proper noun World Wide Web) is a collection of Web pages Client-side JavaScript ( CSJS) is JavaScript that runs on Client-side, i

JavaScript, despite the name, is essentially unrelated to the Java programming language, although both have the common C syntax, and JavaScript copies many Java names and naming conventions. tags please moot on the talk page first! --> In Computing, C is a general-purpose cross-platform block structured Curly brace or bracket Programming languages are those which use Balanced Brackets ( { and }, also known as "squiggly The language was originally named "LiveScript" but was renamed in a co-marketing deal between Netscape and Sun, in exchange for Netscape bundling Sun's Java runtime with their then-dominant browser. Netscape Communications (formerly known as Netscape Communications Corporation and commonly known as Netscape) is an American computer services company Sun Microsystems Inc ( is a multinational vendor of Computers computer components Computer software, and Information technology services A web browser is a software application which enables a user to display and interact with text images videos music games and other information typically located on a The key design principles within JavaScript are inherited from the Self programming language. Self is an object-oriented programming language based on the concept of prototypes.

"JavaScript" is a trademark of Sun Microsystems. A trademark or trade mark, represented by the symbols ™ and ®, or mark is a distinctive sign or indicator used by an individual It was used under license for technology invented and implemented by Netscape Communications and current entities such as the Mozilla Foundation. The Mozilla Foundation is a Non-profit organization that exists to support and provide leadership for the Open source Mozilla project ^[3]

History and naming

Some JavaScript source code

JavaScript was originally developed by Brendan Eich of Netscape under the name Mocha, which was later renamed to LiveScript, and finally to JavaScript. Brendan Eich (born 1961 is a Computer programmer and creator of the JavaScript Programming language. The language was originally implemented in Common Lisp (and retains many Lisp-like qualities). Common Lisp, commonly abbreviated CL, is a dialect of the Lisp Programming language, published in ANSI standard document Information ^[4] The change of name from LiveScript to JavaScript roughly coincided with Netscape adding support for Java technology in its Netscape Navigator web browser. Netscape Navigator and Netscape are the names for the proprietary Web browser popular in the 1990s and the Flagship product of the Netscape A web browser is a software application which enables a user to display and interact with text images videos music games and other information typically located on a JavaScript was first introduced and deployed in the Netscape browser version 2. 0B3 in December 1995. Events in December Union Day of Romania (1 December World AIDS Day ( December 1) National Day of Year 1995 ( MCMXCV) was a Common year starting on Sunday. Events of 1995 The naming has caused confusion, giving the impression that the language is a spin-off of Java, and it has been characterized by many as a marketing ploy by Netscape to give JavaScript the cachet of what was then the hot new web-programming language. ^[5][6]

Microsoft named its dialect of the language JScript to avoid trademark issues. Microsoft Corporation is an American multinational Computer technology Corporation, which rose to dominate the Home computer JScript is the Microsoft dialect of the ECMAScript Scripting language specification JScript was first supported in Internet Explorer version 3. Windows Internet Explorer (formerly Microsoft Internet Explorer abbreviated MSIE) commonly abbreviated to IE, is a series of graphical 0, released in August 1996, and it included Y2K compliant date functions, unlike those based on java.util.Date in JavaScript at the time. The Year 2000 problem (also known as the Y2K problem, the millennium bug, the Y2K bug, or simply Y2K) was a notable Computer bug resulting The dialects are perceived to be so similar that the terms "JavaScript" and "JScript" are often used interchangeably (including in this article). Microsoft, however, notes dozens of ways in which JScript is not ECMA compliant.

Netscape submitted JavaScript to Ecma International for standardization resulting in the standardized version named ECMAScript. Ecma International (Ecma is an international private (membership-based non-profit Standards organization for information and communication systems ECMAScript is a Scripting language, standardized by Ecma International in the ECMA-262 specification. ^[7]

Features

Structured programming

JavaScript supports all the structured programming syntax in C (e. Structured programming can be seen as a subset or subdiscipline of Procedural programming, one of the major Programming paradigms It is most famous for removing or tags please moot on the talk page first! --> In Computing, C is a general-purpose cross-platform block structured g. , if statements, while loops, switch statements, etc. ). One partial exception is scoping: C-style block-level scoping is not supported. In Computer programming, scope is an enclosing context where values and expressions are associated However, JavaScript 1. 7 supports block-level scoping with the let keyword.

Dynamic programming

dynamic typing

As in most scripting languages, types are associated with values, not variables. In Computer science, a type system defines how a Programming language classifies values and expressions into '''types''', how it can In Computer science, a value is a sequence of Bits that is interpreted according to some Data type. A variable (ˈvɛərɪəbl is an Attribute of a physical or an abstract System which may change its Value while it is under Observation. For example, a variable x could be bound to a number, then later rebound to a string. In Computer programming and some branches of Mathematics, a string is an ordered Sequence of Symbols. JavaScript supports various ways to test the type of an object, including duck typing. In Computer programming, duck typing is a style of Dynamic typing in which an object's current set of methods and properties determines the valid

objects as associative arrays

JavaScript is heavily object-based. Objects are associative arrays, such that object property names are associative array keys. In its simplest embodiment an object is an allocated region of storage An associative array (also associative container, map, mapping, hash, dictionary, finite map, and in query-processing an obj. x = 10 and obj["x"] = 10 are equivalent, the dot notation being merely syntactic sugar. Syntactic sugar is a term coined by Peter J Landin for additions to the Syntax of a Computer language that do not affect its functionality Properties and their values can be added, changed, or deleted at run-time. The properties of an object can also be enumerated via a for. . . in loop.

interpreted

Conforming JavaScript engines must be able to interpret (as opposed to compile) source code. In Computer science, an interpreter normally means a Computer program that executes, i This allows JavaScript to include an eval function. In some Programming languages eval is a function which eval uates a string as though it were an expression and returns a result in others it executes

Function-level programming

first-class functions

Functions are first-class; they are objects themselves. In Computer science, a subroutine ( function, method, procedure, or subprogram) is a portion of code within a larger In Computer science, a Programming language is said to support first-class functions (or function literal) if it treats functions as As such, they have properties and can be passed around and interacted with like any other object.

inner functions and closures

Inner functions (functions defined within other functions) are created each time the outer function is invoked, and variables of the outer functions for that invocation continue to exist as long as the inner functions still exist, even after that invocation is finished (e. g. if the inner function was returned, it still has access to the outer function's variables) — this is the mechanism behind closures within JavaScript. In Computer science, a closure is a function that is evaluated in an environment containing one or more Bound variables When called the function can access

Prototype-based

prototypes

JavaScript uses prototypes instead of classes for defining object properties, including methods, and inheritance. Prototype-based programming is a style of Object-oriented programming in which classes are not present and behavior reuse (known as inheritance in class-based In Object-oriented programming, a class is a Programming language construct that is used as a blueprint to create objects This blueprint includes attributes In Object-oriented programming, the term method refers to a Subroutine that is exclusively associated either with a class (called class methods In Object-oriented programming, inheritance is a way to form new classes (instances of which are called objects using classes that have already been defined It is possible to simulate many class-based features with prototypes in JavaScript.

functions as object constructors

Functions double as object constructors along with their typical role. Prefixing a function call with new creates a new object and calls that function with its local this keyword bound to that object for that invocation. The function's prototype property determines the new object's prototype.

functions as methods

Unlike many object-oriented languages, there is no distinction between a function definition and a method definition. In Object-oriented programming, the term method refers to a Subroutine that is exclusively associated either with a class (called class methods Rather, the distinction occurs during function calling; a function can be called as a method. When a function is invoked as a method of an object, the function's local this keyword is bound to that object for that invocation.

Others

run-time environment

JavaScript typically relies on a run-time environment (e. g. in a web browser) to provide objects and methods by which scripts can interact with "the outside world". (This is not a language feature per se, but it is common in most JavaScript implementations. )

variadic functions

An indefinite number of parameters can be passed to a function. The function can both access them through formal parameters and the local arguments object. In Mathematics, Statistics, and the mathematical Sciences a parameter ( G auxiliary measure) is a quantity that defines certain characteristics

regular expressions

JavaScript also supports regular expressions in a manner similar to Perl, which provide a concise and powerful syntax for text manipulation that is more sophisticated than the built-in string functions. In Computing, regular expressions provide a concise and flexible means for identifying strings of text of interest such as particular characters words or patterns of characters NOTES FOR EDITORS "Perl" is not an acronym (read the "Name" section below

Syntax

Further information: JavaScript syntax

As of 2008, the latest version of the language is JavaScript 1. The Syntax of JavaScript is a set of rules that defines what constitutes a valid program in the Javascript language 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common 8. The previous version 1. 6 corresponded to ECMA-262 Edition 3 like JavaScript 1. ECMAScript is a Scripting language, standardized by Ecma International in the ECMA-262 specification. 5, except for Array extras, and Array and String generics. ECMAScript, in simple terms, is a standardized version of JavaScript. ECMAScript is a Scripting language, standardized by Ecma International in the ECMA-262 specification. The ECMA-357 standard specifies E4X, a language extension dealing with XML. ECMAScript for XML ( E4X) is a programming language extension that adds native XML support to ECMAScript (which includes ActionScript, DMDScript Don't change "Extensible"

Use in web pages

See also: Ajax (programming)

The primary use of JavaScript is to write functions that are embedded in or included from HTML pages and interact with the Document Object Model (DOM) of the page. HTML, an initialism of HyperText Markup Language, is the predominant Markup language for Web pages It provides a means to describe the structure The Document Object Model ( DOM) is a platform- and language -independent standard Object model for representing HTML or XML and related Some simple examples of this usage are:

• Opening or popping up a new window with programmatic control over the size, position and 'look' of the new window (i. Pop-up ads or popups are a form of online advertising on the World Wide Web intended to attract Web traffic or capture email addresses e. whether the menus, toolbars, etc. are visible).
• Validation of web form input values to make sure that they will be accepted before they are submitted to the server. A webform on a Web page allows a user to enter data that is typically sent to a server for processing and to mimic the usage of paper forms.
• Changing images as the mouse cursor moves over them: This effect is often used to draw the user's attention to important links displayed as graphical elements. Rollover refers to a button as created by a web developer or web designer found within a Web page, used to provide interactivity between the user and the page itself

Because JavaScript code can run locally in a user's browser (rather than on a remote server), it can respond to user actions quickly, making an application feel more responsive. Furthermore, JavaScript code can detect user actions which HTML alone cannot, such as individual keystrokes. Applications such as Gmail take advantage of this: much of the user-interface logic is written in JavaScript, and JavaScript dispatches requests for information (such as the content of an e-mail message) to the server. Gmail, officially Google Mail in Germany and the United Kingdom is a free POP3 and IMAP The wider trend of Ajax programming similarly exploits this strength.

A JavaScript engine (also known as JavaScript interpreter or JavaScript implementation) is an interpreter that interprets JavaScript source code and executes the script accordingly. In Computer science, an interpreter normally means a Computer program that executes, i In Computer science, source code (commonly just source or code) is any sequence of statements or declarations written in some Human-readable Computer programs (also software programs, or just programs) are instructions for a Computer. The first ever JavaScript engine was created by Brendan Eich at Netscape Communications Corporation, for the Netscape Navigator web browser. Brendan Eich (born 1961 is a Computer programmer and creator of the JavaScript Programming language. Netscape Communications (formerly known as Netscape Communications Corporation and commonly known as Netscape) is an American computer services company Netscape Navigator and Netscape are the names for the proprietary Web browser popular in the 1990s and the Flagship product of the Netscape A web browser is a software application which enables a user to display and interact with text images videos music games and other information typically located on a The engine, code-named SpiderMonkey, is implemented in C. tags please moot on the talk page first! --> In Computing, C is a general-purpose cross-platform block structured It has since been updated (in JavaScript 1. 5) to conform to ECMA-262 Edition 3. The Rhino engine, created primarily by Norris Boyd (also at Netscape) is a JavaScript implementation in Java. Rhino is an Open source JavaScript engine. It is developed entirely in Java and managed by the Mozilla Foundation. Like SpiderMonkey, Rhino is ECMA-262 Edition 3 compliant.

By far, the most common host environment for JavaScript is a web browser. Web browsers typically use the public API to create "host objects" responsible for reflecting the DOM into JavaScript. The Document Object Model ( DOM) is a platform- and language -independent standard Object model for representing HTML or XML and related The web server is another common application of the engine. The term web server can mean one of two things A Computer program that is responsible for accepting HTTP requests from web clients which are A JavaScript webserver would expose host objects representing an HTTP request and response objects, which a JavaScript program could then manipulate to dynamically generate web pages. Server-side JavaScript ( SSJS) refers to JavaScript that runs on Server-side. Hypertext Transfer Protocol ( HTTP) is a Communications protocol for the transfer of information on the Internet.

A minimal example of a web page containing JavaScript (using HTML 4.01 syntax) would be:

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4. HTML, an initialism of HyperText Markup Language, is the predominant Markup language for Web pages It provides a means to describe the structure 01//EN"
"http://www. w3. org/TR/html4/strict. dtd">
<html>
  <head><title>simple page</title></head>
  <body>
    <script type="text/javascript">
      document. write('Hello World!');
    </script>
    <noscript>
      <p>Your browser either does not support JavaScript, or you have JavaScript turned off. </p>
    </noscript>
  </body>
</html>

Compatibility considerations

Main articles: Web Interoperability and Web accessibility

The DOM interfaces for manipulating web pages are not part of the ECMAScript standard, or of JavaScript itself. Web interoperability means producing web pages viewable in standard compatible Web browsers various Operating systems such as Windows, Macintosh Web accessibility refers to the practice of making Websites usable by people of all abilities and Disabilities. The Document Object Model ( DOM) is a platform- and language -independent standard Object model for representing HTML or XML and related Officially, they are defined by a separate standardization effort by the W3C; in practice, browser implementations differ from the standards and from each other, and not all browsers execute JavaScript.

To deal with these differences, JavaScript authors can attempt to write standards-compliant code which will also be executed correctly by most browsers; failing that, they can write code that checks for the presence of certain browser features and behaves differently if they are not available. ^[8] In some cases, two browsers may both implement a feature but with different behavior, and authors may find it practical to detect what browser is running and change their script's behavior to match. ^[9][10] Programmers may also use libraries or toolkits which take browser differences into account.

Furthermore, scripts will not work for all users. For example, a user may:

• use an old or rare browser with incomplete or unusual DOM support,
• use a PDA or mobile phone browser which cannot execute JavaScript,
• have JavaScript execution disabled as a security precaution,
• or be visually or otherwise disabled and use a speech browser

To support these users, web authors can try to create pages which degrade gracefully on user agents (browsers) which do not support the page's JavaScript. This article contains specific implementations of fault tolerant systems

Security

JavaScript and the DOM provide the potential for malicious authors to deliver scripts to run on a client computer via the web. Browser authors contain this risk using two restrictions. First, scripts run in a sandbox in which they can only perform web-related actions, not general-purpose programming tasks like creating files. This article is about the Computer security mechanism For the Wikipedia feature where newcomers can experiment with editing or established editors can experiment with Second, scripts are constrained by the same origin policy: scripts from one web site do not have access to information such as usernames, passwords, or cookies sent to another site. In Computing, the same origin policy is an important security measure for Client-side scripting (mostly JavaScript) Most JavaScript-related security bugs are breaches of either the same origin policy or the sandbox. In Computing, the same origin policy is an important security measure for Client-side scripting (mostly JavaScript) This article is about the Computer security mechanism For the Wikipedia feature where newcomers can experiment with editing or established editors can experiment with

Cross-site vulnerabilities

Main articles: Cross-site scripting and Cross-site request forgery

A common JavaScript-related security problem is cross-site scripting, or XSS, a violation of the same origin policy. Cross-site scripting ( XSS) is a type of computer security vulnerability typically found in Web applications which allow Code injection Cross-site request forgery, also known as one-click attack, sidejacking or session riding and abbreviated as CSRF (Sea-Surf Contrary to Cross-site scripting ( XSS) is a type of computer security vulnerability typically found in Web applications which allow Code injection In Computing, the same origin policy is an important security measure for Client-side scripting (mostly JavaScript) XSS vulnerabilities occur when an attacker is able to cause a trusted web site, such as an online banking website, to include a malicious script in the webpage presented to a victim. In that example, the script can then access the banking application with the privileges of the victim, potentially disclosing secret information or transferring money without the victim's authorization.

XSS vulnerabilities can also occur because of implementation mistakes by browser authors. ^[11]

XSS is related to, but not the same as, cross-site request forgery or XSRF. Cross-site request forgery, also known as one-click attack, sidejacking or session riding and abbreviated as CSRF (Sea-Surf Contrary to In XSRF, one website causes a victim's browser to generate fraudulent requests to another site, with the victim's legitimate HTTP cookies attached to the request. HTTP cookies, or more commonly referred to as Web cookies tracking cookies or just cookies are parcels of text sent by a server to a Web client (usually

Misunderstanding the client-server boundary

Client-server applications, whether they involve JavaScript or not, must assume that untrusted clients may be under the control of attackers. Thus any secret embedded in JavaScript could be extracted by a determined adversary, and the output of JavaScript operations should not be trusted by the server. Some implications:

• Web site authors cannot perfectly conceal how their JavaScript operates, because the code is sent to the client, and obfuscated code can be reverse engineered. Obfuscated code is Source code or Intermediate language that is very hard to read and understand often intentionally
• JavaScript form validation only provides convenience for users, not security. If a site verifies that the user agreed to its terms of service, or filters invalid characters out of fields that should only contain numbers, it must do so on the server, not only the client.
• It would be extremely bad practice to embed a password in JavaScript (where it can be extracted by an attacker), then have JavaScript verify a user's password and pass "password_ok=1" back to the server (since the "password_ok=1" response is easy to forge). ^[12]

Browser and plugin coding errors

JavaScript provides an interface to a wide range of browser capabilities, some of which may have flaws such as buffer overflows. These flaws can allow attackers to write scripts which would run any code they wish on the user's system.

These flaws have affected major browsers including Firefox^[13], Internet Explorer^[14], and Safari. ^[15]

Plugins, such as video players, Macromedia Flash, and the wide range of ActiveX controls enabled by default in Microsoft Internet Explorer, may also have flaws exploitable via JavaScript, and such flaws have been exploited in the past. Adobe Flash (previously called Shockwave Flash and Macromedia Flash) is a set of Multimedia software created by Macromedia and currently ActiveX is a Component object model (COM developed by Microsoft for Windows. ^[16][17] In Windows Vista, Microsoft has attempted to contain the risks of bugs such as buffer overflows by running the Internet Explorer process with limited privileges. ^[18]

Sandbox implementation errors

Web browsers are capable of running JavaScript outside of the sandbox, with the privileges necessary to, for example, create or delete files. Of course, such privileges aren't meant to be granted to code from the web.

Incorrectly granting privileges to JavaScript from the web has played a role in vulnerabilities in both Internet Explorer^[19] and Firefox^[20]. In Windows XP Service Pack 2, Microsoft tightened the rules on what JScript would be run with high privileges by Internet Explorer. ^[21]

Some versions of Microsoft Windows allow JavaScript stored on a computer's hard drive to run as a general-purpose, non-sandboxed program. Microsoft Windows is a series of Software Operating systems and Graphical user interfaces produced by Microsoft. This makes JavaScript (like VBScript) a theoretically viable vector for a Trojan horse, although JavaScript Trojan horses are uncommon in practice. VBScript (short for Visual Basic Scripting Edition) is an Active Scripting language developed by Microsoft. This article refers to a form of Malware in computing terminology ^[22] (See Windows Script Host. The Microsoft Windows Script Host (originally called Windows Scripting Host, but renamed for the second release is distributed and installed by default on Windows )

Uses outside web pages

Outside the web, JavaScript interpreters are embedded in a number of tools. Each of these applications provides its own object model which provides access to the host environment, with the core JavaScript language remaining mostly the same in each application. In Computing, object model has two related but distinct meanings The properties of objects in general in a specific computer Programming language

• ActionScript, the programming language used in Adobe Flash, is another implementation of the ECMAScript standard. ActionScript is a scripting language based on ECMAScript. ActionScript is used primarily for the development of websites and software using the Adobe Flash Player Adobe Flash (previously called Shockwave Flash and Macromedia Flash) is a set of Multimedia software created by Macromedia and currently
• Apple's Dashboard Widgets, Microsoft's Gadgets, and Yahoo! Widgets are implemented using JavaScript. Dashboard is an application for Apple 's Mac OS X operating systems used for hosting mini-applications known as widgets. Microsoft Gadgets are light-weight single-purpose applications that can sit on the user's computer desktop or are hosted on a web page Yahoo! Widgets is a free application platform for Mac OS X and Microsoft Windows.
• The Mozilla platform, which underlies Firefox and some other web browsers, uses JavaScript to implement the graphical user interface (GUI) of its various products. Mozilla was the official public original name of Mozilla Application Suite by the Mozilla Foundation, currently known as SeaMonkey suite.
• Adobe's Acrobat and Adobe Reader (formerly Acrobat Reader) support JavaScript in PDF files. Adobe Acrobat is a family of computer programs developed by Adobe Systems, designed to view create manipulate and manage files in Adobe's Portable Document
• Tools in the Adobe Creative Suite, including Photoshop, Illustrator, Dreamweaver and InDesign, allow scripting through JavaScript. Adobe Creative Suite is a collection of Graphic design, Video editing, and Web development applications made by Adobe Systems. Adobe Illustrator is a vector-based drawing program developed and marketed by Adobe Systems. Adobe Dreamweaver is a Web development application originally created by Allaire Systems who was acquired approximately 1998 by Macromedia and is now owned Adobe InDesign is a Desktop publishing (DTP software application produced by Adobe Systems.
• Microsoft's Active Scripting technology supports the JavaScript-compatible JScript as an operating system scripting language. Active Scripting (formerly known as ActiveX Scripting) is the technology used in Windows to implement component-based scripting support JScript is the Microsoft dialect of the ECMAScript Scripting language specification
• The Java programming language, in version SE 6 (JDK 1. 6), introduced the javax. script package, based on Mozilla Rhino. Rhino is an Open source JavaScript engine. It is developed entirely in Java and managed by the Mozilla Foundation. Thus, Java applications can host scripts that access the application's variables and objects, much like web browsers host scripts that access the browser's Document Object Model (DOM) for a webpage. ^[23][24]
• Newer versions of the Qt C++ toolkit include a QtScript module to interpret JavaScript, analogous to javax. Qt (pronounced "cute" by its creators is a Cross-platform application development framework widely used for the development of GUI programs (in which script. ^[25]
• The interactive music signal processing software Max/MSP released by Cycling '74, offers a JavaScript model of its environment for use by developers. Max is a graphical Development environment for Music and Multimedia developed and maintained by San Francisco -based software company Cycling It allows much more precise control than the default GUI-centric programming model.
• Late Night Software's JavaScript OSA (aka JavaScript for OSA, or JSOSA), is a freeware alternative to AppleScript for Mac OS X. JavaScript OSA, (originally JavaScript for OSA, abbreviated as JSOSA) is a Freeware Inter-process communication Scripting language AppleScript is a Scripting language devised by Apple Inc, and built into Mac OS. It is based on the Mozilla 1. 5 JavaScript implementation, with the addition of a MacOS object for interaction with the operating system and third-party applications. ^[26]
• ECMAScript was included in the VRML97 standard for scripting nodes of VRML scene description files. VRML ( Virtual Reality Modeling Language, pronounced vermal or by its initials originally — before 1995 — known as the Virtual Reality Markup Language
• Some high-end Philips universal remote panels, including TSU9600 and TSU9400, can be scripted using JavaScript. A universal remote is a Remote control that can be programmed to operate various brands of one or more types of Consumer electronics devices ^[27]
• Sphere^[28] is an open source and cross platform computer program designed primarily to make role-playing games that uses JavaScript as scripting language.
• Adobe Integrated Runtime is a JavaScript runtime that allows developers to create desktop applications. Adobe AIR is a Cross-platform Runtime environment for building

Debugging

Within JavaScript, access to a debugger becomes invaluable when developing large, non-trivial programs. A debugger is a Computer program that is used to test and Debug other programs Because there can be implementation differences between the various browsers (particularly within the Document Object Model) it is useful to have access to a debugger for each of the browsers a web application is being targeted at. The Document Object Model ( DOM) is a platform- and language -independent standard Object model for representing HTML or XML and related

Currently, Internet Explorer, Firefox, Safari, and Opera all have script debuggers available for them. Windows Internet Explorer (formerly Microsoft Internet Explorer abbreviated MSIE) commonly abbreviated to IE, is a series of graphical Safari is a Web browser developed by Apple Inc and included in Mac OS X. Opera is a Web browser and Internet suite developed by the Opera Software company

Internet Explorer has three debuggers available for it: Microsoft Visual Studio is the richest of the three, closely followed by Microsoft Script Editor (a component of Microsoft Office^[29]), and finally the free Microsoft Script Debugger which is far more basic than the other two. Microsoft Visual Studio is the main Integrated Development Environment (IDE from Microsoft. Microsoft Office is a set of interrelated desktop applications servers and services collectively referred to as an Office suite, for the Microsoft Windows and Microsoft Script Debugger is lightweight debugger for Windows Script Host -supported scripting languages such as VBScript and JScript. The free Microsoft Visual Web Developer Express provides a limited version of the JavaScript debugging functionality in Microsoft Visual Studio.

Web applications within Firefox can be debugged using the Firebug plug-in, or the older Venkman debugger, which also works with the Mozilla browser. The Firebug extension for Mozilla Firefox allows the debugging editing and monitoring of any website's CSS HTML DOM and JavaScript and provides other web development tools Venkman is the JavaScript Debugger component of the Mozilla Application Suite. Mozilla was the official public original name of Mozilla Application Suite by the Mozilla Foundation, currently known as SeaMonkey suite. Drosera is a debugger for the WebKit engine^[30] on Macintosh and Windows^[31] powering Apple's Safari. WebKit is an Open source Application framework that provides a foundation upon which to build a Web browser. Safari is a Web browser developed by Apple Inc and included in Mac OS X.

There are also some free tools such as JSLint, a code quality tool that will scan JavaScript code looking for problems^[32], as well as a non-free tool called SplineTech JavaScript HTML Debugger. ^[33]

Since JavaScript is interpreted, loosely-typed, and may be hosted in varying environments, each with their own compatibility differences, a programmer has to take extra care to make sure the code executes as expected in as wide a range of circumstances as possible, and that functionality degrades gracefully when it does not.

Versions

The next major version of JavaScript, 2. 0, will conform to ECMA-262 4^th edition. ECMAScript is a Scripting language, standardized by Ecma International in the ECMA-262 specification. ^[34]

Related languages

There is not a particularly close genealogical relationship between Java and JavaScript; their similarities are mostly in basic syntax because both are ultimately derived from C. Their semantics are quite different and their object models are unrelated and largely incompatible. In Java, as in C and C++, all data is statically typed, whereas JavaScript variables, properties, and array elements may hold values of any type. In Computer science, a type system defines how a Programming language classifies values and expressions into '''types''', how it can

The standardization effort for JavaScript also needed to avoid trademark issues, so the ECMA 262 standard calls the language ECMAScript, three editions of which have been published since the work started in November 1996. ECMAScript is a Scripting language, standardized by Ecma International in the ECMA-262 specification.

Microsoft's VBScript, like JavaScript, can be run client-side in web pages. VBScript (short for Visual Basic Scripting Edition) is an Active Scripting language developed by Microsoft. VBScript has syntax derived from Visual Basic and is only supported by Microsoft's Internet Explorer. Visual Basic ( VB) is the third-generation event-driven programming language and associated development environment (IDE from

JSON, or JavaScript Object Notation, is a general-purpose data interchange format that is defined as a subset of JavaScript. JSON (ˈdʒeɪsɒn ie "Jason" short for JavaScript Object Notation, is a lightweight Computer data interchange format

JavaScript is also considered a functional programming language like Scheme and OCaml because it has closures and supports higher-order functions. In Computer science, functional programming is a Programming paradigm that treats Computation as the evaluation of mathematical functions and Scheme is a Multi-paradigm programming language. It is one of the two main dialects of Lisp and supports a number of programming paradigms but is Objective Caml ( OCaml) is the main implementation of the Caml Programming language, created by Xavier Leroy, Jérôme Vouillon In Computer science, a closure is a function that is evaluated in an environment containing one or more Bound variables When called the function can access In Mathematics and Computer science, higher-order functions or '''functionals''' are functions which do at least one of the following ^[35]

See also

References

Bibliography

External links

• Mozilla's Official Documentation on JavaScript
• References for Core JavaScript versions: 1.5
• New in JavaScript: 1.7, 1.6
• List of JavaScript releases: versions 1.0 - 1.7
• Re-Introduction to JavaScript
• JavaScript at the Open Directory Project
• John Resig: Versions of JavaScript
• Eloquent JavaScript An opinionated introduction to JavaScript, with online interpreter