 Unofficial logo from JSConf EU 2011 |
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| Paradigm(s) | Multi-paradigm: scripting, object-oriented (prototype-based), imperative, functional[1] |
|---|---|
| Appeared in | 1995 |
| Designed by | Brendan Eich |
| Developer | Netscape Communications Corporation, Mozilla Foundation |
| Stable release | 1.8.5[2] (March 22, 2011 ) |
| Typing discipline | dynamic, weak, duck |
| Major implementations | KJS, Rhino, SpiderMonkey, V8, WebKit, Carakan, Chakra |
| Influenced by | C, Java, Perl, Python, Scheme, Self |
| Influenced | ActionScript, CoffeeScript, Dart, JScript .NET, Objective-J, QML, TIScript |
 JavaScript at Wikibooks |
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| Filename extension | .js |
|---|---|
| Internet media type | application/javascripttext/javascript (obsolete)[3] |
| Uniform Type Identifier | com.netscape.javascript-source[4] |
| Type of format | Scripting language |
| Part of a series on |
| JavaScript |
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JavaScript (sometimes abbreviated JS) is a prototype-based scripting language that is dynamic, weakly typed and has first-class functions. It is a multi-paradigm language, supporting object-oriented,[5] imperative, and functional[1][6] programming styles.
JavaScript was formalized in the ECMAScript language standard and is primarily used in the form of client-side JavaScript, implemented as part of a Web browser in order to provide enhanced user interfaces and dynamic websites. This enables programmatic access to computational objects within a host environment.
JavaScript's use in applications outside Web pages — for example in PDF documents, site-specific browsers, and desktop widgets — is also significant. Newer and faster JavaScript VMs and frameworks built upon them (notably Node.js) have also increased the popularity of JavaScript for server-side web applications.
JavaScript uses syntax influenced by that of C. JavaScript copies many names and naming conventions from Java, but the two languages are otherwise unrelated and have very different semantics. The key design principles within JavaScript are taken from the Self and Scheme programming languages.[7]
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Anyway, I know only one programming language worse than C and that is Javascript. [...] I was convinced that we needed to build-in a programming language, but the developers, Tim first, were very much opposed. It had to remain completely declarative. Maybe, but the net result is that the programming-vacuum filled itself with the most horrible kluge in the history of computing: Javascript.
JavaScript was originally developed in Netscape, by Brendan Eich. Battling with Microsoft over the Internet, Netscape considered their client-server solution as a distributed OS, running a portable version of Sun Microsystem's Java. Because Java was a competitor of C++ and aimed at professional programmers, Netscape also wanted a lightweight interpreted language that would complement Java by appealing to nonprofessional programmers, like Microsoft's VB.[9] (see JavaScript and Java)
Developed under the name Mocha, LiveScript was the official name for the language when it first shipped in beta releases of Netscape Navigator 2.0 in September 1995, but it was renamed JavaScript in a joint announcement with Sun Microsystems on December 4, 1995,[10] when it was deployed in the Netscape browser version 2.0B3.[11]
The change of name from LiveScript to JavaScript roughly coincided with Netscape adding support for Java technology in its Netscape Navigator web browser. The final choice of name caused confusion, giving the impression that the language was a spin-off of the Java programming language, and the choice 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.[12][13] It has also been claimed that the language's name is the result of a co-marketing deal between Netscape and Sun, in exchange for Netscape bundling Sun's Java runtime with its then-dominant browser.
Netscape introduced an implementation of the language for server-side scripting with Netscape Enterprise Server, first released in December, 1994 (soon after releasing JavaScript for browsers).[14][15] Since the mid-2000s, there has been a proliferation of server-side JavaScript implementations, with node.js being merely one example.[16][17]
JavaScript very quickly gained widespread success as a client-side scripting language for web pages. Microsoft introduced JavaScript support in its own web browser, Internet Explorer, in version 3.0, released in August 1996.[18][not in citation given] Microsoft's webserver, Internet Information Server, introduced support for server-side scripting in JavaScript with release 3.0 (1996). Microsoft started to promote webpage scripting using the umbrella term Dynamic HTML.
Microsoft's JavaScript implementation was later renamed to JScript to avoid trademark issues. JScript added new date methods to fix the Y2K-problematic methods in JavaScript, which were based on Java's java.util.Date class.
In November 1996, Netscape announced that it had submitted JavaScript to Ecma International for consideration as an industry standard, and subsequent work resulted in the standardized version named ECMAScript.[19]
JavaScript has become one of the most popular programming languages on the web. Initially, however, many professional programmers denigrated the language because its target audience was web authors and other such "amateurs", among other reasons.[20] The advent of Ajax returned JavaScript to the spotlight and brought more professional programming attention. The result was a proliferation of comprehensive frameworks and libraries, improved JavaScript programming practices, and increased usage of JavaScript outside of web browsers, as seen by the proliferation of server-side JavaScript platforms.
In January 2009, the CommonJS project was founded with the goal of specifying a common standard library mainly for JavaScript development outside the browser.[21]
Today, "JavaScript" is a trademark of Oracle Corporation.[22] It is used under license for technology invented and implemented by Netscape Communications and current entities such as the Mozilla Foundation.[23]
The following features are common to all conforming ECMAScript implementations, unless explicitly specified otherwise.
JavaScript supports much of the structured programming syntax from C (e.g., if statements, while loops, switch statements, etc.). One partial exception is scoping: C-style block-level scoping is not supported (instead, JavaScript has function-level scoping). JavaScript 1.7, however, supports block-level scoping with the let keyword. Like C, JavaScript makes a distinction between expressions and statements. One syntactic difference from C is automatic semicolon insertion, in which the semicolons that terminate statements can be omitted.[24]
x could be bound to a number, then later rebound to a string. JavaScript supports various ways to test the type of an object, including duck typing.[25]obj.x = 10 and obj['x'] = 10 are equivalent, the dot notation being syntactic sugar. Properties and their values can be added, changed, or deleted at run-time. Most properties of an object (and those on its prototype inheritance chain) can be enumerated using a for...in loop. JavaScript has a small number of built-in objects such as Function and Date.eval function that can execute statements provided as strings at run-time.length and call();[26] and they can be assigned to variables, passed as arguments, returned by other functions, and manipulated like any other object.[27] Any reference to a function allows it to be invoked using the () operator.[28]new creates a new object and calls that function with its local this keyword bound to that object for that invocation. The constructor's prototype property determines the object used for the new object's internal prototype. JavaScript's built-in constructors, such as Array, also have prototypes that can be modified.this keyword is bound to that object for that invocation.<script> elements). (This is not a language feature per se, but it is common in most JavaScript implementations.)arguments object.JavaScript is officially managed by Mozilla Foundation, and new language features are added periodically. However, only some non-Mozilla JavaScript engines support these new features:
catch clauseslet keywordfunction(args) expr)As of 2011[update], the latest version of the language is JavaScript 1.8.5. It is a superset of ECMAScript (ECMA-262) Edition 3. Extensions to the language, including partial ECMAScript for XML (E4X) (ECMA-357) support and experimental features considered for inclusion into future ECMAScript editions, are documented here.[32]
There is no built-in I/O functionality in JavaScript; the runtime environment provides that. In a web browser, here is the simplest "hello world" example: <syntaxhighlight lang="javascript"> alert("Hello world!"); </syntaxhighlight>
A simple recursive function: <syntaxhighlight lang="javascript"> function factorial(n) {
if (n === 0) {
return 1;
}
return n * factorial(n - 1);
} </syntaxhighlight>
Anonymous function (or lambda) syntax and closure example: <syntaxhighlight lang="javascript"> function displayClosure() {
var count = 0;
return function () {
return ++count;
};
} var inc = displayClosure(); inc(); // returns 1 inc(); // returns 2 inc(); // returns 3 </syntaxhighlight>
Variadic function demonstration (arguments is a special variable). <syntaxhighlight lang="javascript"> function sum() {
var i, x = 0;
for (i = 0; i < arguments.length; ++i) {
x += arguments[i];
}
return x;
} sum(1, 2, 3); // returns 6 </syntaxhighlight>
This sample code showcases various JavaScript features.
<syntaxhighlight lang="javascript"> /* Finds the lowest common multiple of two numbers */ function LCMCalculator(x, y) { // constructor function
var checkInt = function (x) { // inner function
if (x % 1 !== 0) {
throw new TypeError(x + " is not an integer"); // throw an exception
}
return x;
};
this.a = checkInt(x);
// ^ semicolons are optional
this.b = checkInt(y);
} // The prototype of object instances created by a constructor is // that constructor's "prototype" property. LCMCalculator.prototype = { // object literal
constructor: LCMCalculator, // when reassigning a prototype, set the constructor property appropriately
gcd: function () { // method that calculates the greatest common divisor
// Euclidean algorithm:
var a = Math.abs(this.a), b = Math.abs(this.b), t;
if (a < b) {
// swap variables
t = b;
b = a;
a = t;
}
while (b !== 0) {
t = b;
b = a % b;
a = t;
}
// Only need to calculate GCD once, so "redefine" this method.
// (Actually not redefinition - it's defined on the instance itself,
// so that this.gcd refers to this "redefinition" instead of LCMCalculator.prototype.gcd.)
// Also, 'gcd' === "gcd", this['gcd'] === this.gcd
this['gcd'] = function () {
return a;
};
return a;
},
// Object property names can be specified by strings delimited by double (") or single (') quotes.
"lcm" : function () {
// Variable names don't collide with object properties, e.g. |lcm| is not |this.lcm|.
// not using |this.a * this.b| to avoid FP precision issues
var lcm = this.a / this.gcd() * this.b;
// Only need to calculate lcm once, so "redefine" this method.
this.lcm = function () {
return lcm;
};
return lcm;
},
toString: function () {
return "LCMCalculator: a = " + this.a + ", b = " + this.b;
}
};
//define generic output function; this implementation only works for web browsers function output(x) {
document.write(x + "
");
}
// Note: Array's map() and forEach() are defined in JavaScript 1.6. // They are used here to demonstrate JavaScript's inherent functional nature. [[25, 55], [21, 56], [22, 58], [28, 56]].map(function (pair) { // array literal + mapping function
return new LCMCalculator(pair[0], pair[1]);
}).sort(function (a, b) { // sort with this comparative function
return a.lcm() - b.lcm();
}).forEach(function (obj) {
output(obj + ", gcd = " + obj.gcd() + ", lcm = " + obj.lcm());
}); </syntaxhighlight>
The following output should be displayed in the browser window.
<syntaxhighlight lang="html4strict"> LCMCalculator: a = 28, b = 56, gcd = 28, lcm = 56
LCMCalculator: a = 21, b = 56, gcd = 7, lcm = 168
LCMCalculator: a = 25, b = 55, gcd = 5, lcm = 275
LCMCalculator: a = 22, b = 58, gcd = 2, lcm = 638
</syntaxhighlight>
The most common use of JavaScript is to write functions that are embedded in or included from HTML pages and that interact with the Document Object Model (DOM) of the page. Some simple examples of this usage are:
Because JavaScript code can run locally in a user's browser (rather than on a remote server), the browser can respond to user actions quickly, making an application 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. 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. The first JavaScript engine was created by Brendan Eich at Netscape Communications Corporation, for the Netscape Navigator web browser. The engine, code-named SpiderMonkey, is implemented in C. It has since been updated (in JavaScript 1.5) to conform to ECMA-262 Edition 3. The Rhino engine, created primarily by Norris Boyd (formerly of Netscape; now at Google) is a JavaScript implementation in Java. Rhino, like SpiderMonkey, is ECMA-262 Edition 3 compliant.
A web browser is by far the most common host environment for JavaScript. Web browsers typically use the public API to create "host objects" responsible for reflecting the Document Object Model (DOM) into JavaScript. The web server is another common application of the engine. 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.
Because JavaScript is the only language that the most popular browsers share support for, it has become a target language for many frameworks in other languages, even though JavaScript was never intended to be such a language.[34] Despite the performance limitations inherent to its dynamic nature, the increasing speed of JavaScript engines has made the language a surprisingly feasible compilation target.
Below is a minimal example of a standards-conforming web page containing JavaScript (using HTML 4.01 syntax) and the DOM: <syntaxhighlight lang="html4strict"> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//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!');
var h1 = document.getElementById("header"); // holds a reference to the
element </script> <noscript> Your browser either does not support JavaScript, or has JavaScript turned off. </noscript> </body> </html> </syntaxhighlight>
Because JavaScript runs in widely varying environments, an important part of testing and debugging is to test and verify that the JavaScript works across multiple browsers.
The DOM interfaces for manipulating web pages are not part of the ECMAScript standard, or of JavaScript itself. Officially, the DOM interfaces 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.[35] 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.[36][37] Programmers may also use libraries or toolkits which take browser differences into account.
Furthermore, scripts may not work for some users. For example, a user may:
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. In particular, the page should remain usable albeit without the extra features that the JavaScript would have added. An alternative approach that many find preferable is to first author content using basic technologies that work in all browsers, then enhance the content for users that have JavaScript enabled. This is known as progressive enhancement.
Assuming that the user has not disabled its execution, client-side web JavaScript should be written to enhance the experiences of visitors with visual or physical disabilities, and certainly should avoid denying information to these visitors.[38]
Screen readers, used by the blind and partially sighted, can be JavaScript-aware and so may access and read the page DOM after the script has altered it. The HTML should be as concise, navigable and semantically rich as possible whether the scripts have run or not. JavaScript should not be totally reliant on mouse-specific events so as to deny its benefits to users who either cannot use a mouse or who choose to favor the keyboard for whatever reason. Equally, although hyperlinks and webforms can be navigated and operated from the keyboard, accessible JavaScript should not require keyboard events either. There are device-independent events such as onfocus and onchange that are preferable in most cases.[38]
JavaScript should not be used in a way that is confusing or disorienting to any web user. For example, using script to alter or disable the normal functionality of the browser, such as by changing the way the back-button or the refresh event work, is usually best avoided. Equally, triggering events that the user may not be aware of reduces the user's sense of control as do unexpected scripted changes to the page content.[39]
Often the process of making a complex web page as accessible as possible becomes a nontrivial problem where issues become matters of debate and opinion, and where compromises are necessary in the end. However, user agents and assistive technologies are constantly evolving and new guidelines and relevant information are continually being published on the web.[38]
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. 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. Most JavaScript-related security bugs are breaches of either the same origin policy or the sandbox.
A common JavaScript-related security problem is cross-site scripting, or XSS, a violation of the same-origin policy. XSS vulnerabilities occur when an attacker is able to cause a target web site, such as an online banking website, to include a malicious script in the webpage presented to a victim. The script in this example can then access the banking application with the privileges of the victim, potentially disclosing secret information or transferring money without the victim's authorization. A solution to XSS vulnerabilities is to use HTML escaping whenever displaying untrusted data.
Some browsers include partial protection against reflected XSS attacks, in which the attacker provides a URL including malicious script. However, even users of those browsers are vulnerable to other XSS attacks, such as those where the malicious code is stored in a database. Only correct design of Web applications on the server side can fully prevent XSS.
XSS vulnerabilities can also occur because of implementation mistakes by browser authors.[40]
Another cross-site vulnerability is cross-site request forgery or CSRF. In CSRF, code on an attacker's site tricks the victim's browser into taking actions the user didn't intend at a target site (like transferring money at a bank). It works because, if the target site relies only on cookies to authenticate requests, then requests initiated by code on the attacker's site will carry the same legitimate login credentials as requests initiated by the user. In general, the solution to CSRF is to require an authentication value in a hidden form field, and not only in the cookies, to authenticate any request that might have lasting effects. Checking the HTTP Referrer header can also help.
"JavaScript hijacking" is a type of CSRF attack in which a <script> tag on an attacker's site exploits a page on the victim's site that returns private information such as JSON or JavaScript. Possible solutions include:
Developers of client-server applications must recognize 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 application author cannot assume that his JavaScript runs as intended, or at all. Some implications:
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,[42] Internet Explorer,[43] and Safari.[44]
Plugins, such as video players, Adobe 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.[45][46]
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.[47] Google Chrome similarly limits page renderers in its own "sandbox".
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[48] and Firefox.[49] In Windows XP Service Pack 2, Microsoft demoted JScript's privileges in Internet Explorer.[50]
Microsoft Windows allows JavaScript source files on a computer's hard drive to be launched as general-purpose, non-sandboxed programs. This makes JavaScript (like VBScript) a theoretically viable vector for a Trojan horse, although JavaScript Trojan horses are uncommon in practice.[51] (See Windows Script Host.)
In addition to web browsers and servers, 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.
javax.script package, including a JavaScript implementation based on Mozilla Rhino. 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.[61][62]QtScript module to interpret JavaScript, analogous to Java's javax.script package.[63]MacOS object for interaction with the operating system and third-party applications.[64]Within JavaScript, access to a debugger becomes invaluable when developing large, non-trivial 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 that a web application targets.[70]
Script debuggers are available for Internet Explorer, Firefox, Safari, Google Chrome, and Opera.[71]
Three debuggers are available for Internet Explorer: Microsoft Visual Studio is the richest of the three, closely followed by Microsoft Script Editor (a component of Microsoft Office),[72] and finally the free Microsoft Script Debugger which is far more basic than the other two. The free Microsoft Visual Web Developer Express provides a limited version of the JavaScript debugging functionality in Microsoft Visual Studio. Internet Explorer has included developer tools since version 8 (reached by pressing the F12 key).
Web applications within Firefox can be debugged using the Firebug add-on, or the older Venkman debugger. Firefox also has a simpler built-in Error Console, which logs and evaluates JavaScript. It also logs CSS errors and warnings.
Opera includes a set of tools called Dragonfly.[73]
WebKit's Web Inspector includes a JavaScript debugger[74] used in Safari, along with a modified version in Google Chrome.
Some debugging aids are themselves written in JavaScript and built to run on the Web. An example is the program JSLint, developed by Douglas Crockford, currently senior JavaScript architect at Yahoo! who has written extensively on the language. JSLint scans JavaScript code for conformance to a set of standards and guidelines. Web development bookmarklets and Firebug Lite provide variations on the idea of the cross-browser JavaScript console.
MiniME is an open-source JavaScript minifier, obfuscator, and code-checking tool for the .NET platform.
Pretty Diff is an algorithmic diff tool written in JavaScript for comparing white space compressed JavaScript, and several other languages, to human readable forms of similar code.
The following table is based on a history compilation forum post,[75] JQuery author's blog post,[76] and Microsoft's JScript version information webpage.[77]
| Version | Release date | Equivalent to | Netscape Navigator |
Mozilla Firefox |
Internet Explorer |
Opera | Safari | Google Chrome |
|---|---|---|---|---|---|---|---|---|
| 1.0 | March 1996 | 2.0 | 3.0 | |||||
| 1.1 | August 1996 | 3.0 | ||||||
| 1.2 | June 1997 | 4.0-4.05 | ||||||
| 1.3 | October 1998 | ECMA-262 1st + 2nd edition | 4.06-4.7x | 4.0 | ||||
| 1.4 | Netscape Server |
|||||||
| 1.5 | November 2000 | ECMA-262 3rd edition | 6.0 | 1.0 | 5.5 (JScript 5.5), 6 (JScript 5.6), 7 (JScript 5.7), 8 (JScript 5.8) |
6.0 | 3.0-5 | 1.0-10.0.666 |
| 1.6 | November 2005 | 1.5 + array extras + array and string generics + E4X | 1.5 | |||||
| 1.7 | October 2006 | 1.6 + Pythonic generators + iterators + let | 2.0 | |||||
| 1.8 | June 2008 | 1.7 + generator expressions + expression closures | 3.0 | 11.50 | ||||
| 1.8.1 | 1.8 + native JSON support + minor updates | 3.5 | ||||||
| 1.8.2 | June 22, 2009 | 1.8.1 + minor updates | 3.6 | |||||
| 1.8.5 | July 27, 2010 | 1.8.2 + ECMAScript 5 compliance | 4 | 9 | 11.60 |
JSON, or JavaScript Object Notation, is a general-purpose data interchange format that is defined as a subset of JavaScript's literal syntax.
jQuery and Prototype are popular JavaScript libraries designed to simplify DOM-oriented client-side HTML scripting.
Mozilla browsers currently support LiveConnect, a feature that allows JavaScript and Java to intercommunicate on the web. However, Mozilla-specific support for LiveConnect is scheduled to be phased out in the future in favor of passing on the LiveConnect handling via NPAPI to the Java 1.6+ plug-in (not yet supported on the Mac as of March 2010[update]).[78] Most browser inspection tools, such as Firebug in Firefox, include JavaScript interpreters that can act on the visible page's DOM.
As JavaScript is the most widely supported programming language you can run within web browsers, it has become an intermediate language for other languages to target. This has included ports of existing languages, and the creation of new ones. Some of these include:
A common misconception is that JavaScript is similar or closely related to Java. It is true that both have a C-like syntax, the C language being their most immediate common ancestor language. They are both object-oriented, typically sandboxed (when used inside a browser), and are widely used in client-side Web applications. In addition, JavaScript was designed with Java's syntax and standard library in mind. In particular, all Java keywords were reserved in original JavaScript, JavaScript's standard library follows Java's naming conventions, and JavaScript's Math and Date objects are based on classes from Java 1.0.[18]
| “ | JS had to “look like Java” only less so, [it had to] be Java’s dumb kid brother or boy-hostage sidekick. Plus, I had to be done in ten days or something worse than JS would have happened | ” |
However, the similarities end there. Java has static typing; JavaScript's typing is dynamic (meaning a variable can hold an object of any type and cannot be restricted). JavaScript is weakly typed ('0.0000' == 0, 0 == "", false == "", etc.) while Java is more strongly typed. Java is loaded from compiled bytecode; JavaScript is loaded as human-readable source code. Java's objects are class-based; JavaScript's are prototype-based. JavaScript also has many functional features based on the Scheme language.
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Wikiversity has learning materials about Topic:JavaScript |
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| Douglas Crockford | |
|---|---|
 Douglas Crockford at the "Browser Wars: Episode II Attack of the DOMs" event on 2007-02-28 |
|
| Born | Minnesota |
| Alma mater | San Francisco State University |
| Occupation | senior JavaScript architect |
| Employer | PayPal[1] |
| Known for | JavaScript Object Notation |
| Website | |
| crockford.com | |
Douglas Crockford is an American computer programmer and entrepreneur who is best known for his ongoing involvement in the development of the JavaScript language, for having popularized the data format JSON (JavaScript Object Notation), and for developing various JavaScript related tools such as JSLint and JSMin[2]. He is currently a senior JavaScript architect at PayPal, and is also a writer and speaker on JavaScript, JSON, and related web technologies such as the Yahoo! User Interface Library (YUI).
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He earned a degree in Radio and Television from San Francisco State University.[3]
Crockford worked on the computerization of media at Atari, Lucasfilm, and Paramount. He became something of a cult figure on video game oriented listservs in the early 1990s after he posted his memoir "The Expurgation of Maniac Mansion" to a videogaming bulletin board; the memoir documented his efforts to censor the computer game Maniac Mansion to Nintendo's satisfaction so that they could release it as a cartridge, and Crockford's mounting frustrations as Nintendo's demands became more obscure and confusing.[4]
Together with Randy Farmer and Chip Morningstar, Crockford founded Electric Communities and was its CEO from 1994 to 1995. He was involved in the development of the programming language E.
Crockford was also the founder of State Software (also known as Veil Networks) and its CTO from 2001 to 2002.
During his time at State Software, Crockford popularized the JSON data format, based upon existing JavaScript language constructs, as a lightweight alternative to XML. He obtained the domain name json.org in 2002, and put up his description of the format there.[5] In July 2006 he specified the format officially, as RFC 4627.[6]
Peter Seibel interviewed Crockford for his 2009 book Coders at Work, discussing the evolution of JavaScript standards.[7]
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This biographical article relating to a computer specialist is a stub. You can help Wikipedia by expanding it. |
| Dave Herman | |
|---|---|
| Born | September 3, 1941 Bryan, Ohio |
| Position(s) | Tackle |
| College | Michigan State |
| AFL Draft | 1964 |
| Jersey #(s) | 67 |
| Career highlights | |
| AFL All-Star | 1968,1969 |
| Honors | World Champion, 1968 |
| Statistics | |
| Teams | |
| 1964-1969 1970-1973 |
AFL New York Jets NFL New York Jets |
Dave Herman (born September 3, 1941 in Bryan, Ohio) is a former American collegiate and professional football offensive guard. He played collegiately for Michigan State University. He spent his entire 1964-1973 professional career with the New York Jets.
Dave Herman was the starting right guard for the New York Jets during the 1968 season. His fellow starting offensive linemen that year included left tackle Winston Hill, left guard Randy Rasmussen, center John Schmidt, and right tackle Sam Walton.
In preparation for Super Bowl III, Jets coach Weeb Ewbank moved Dave Herman from right guard to right tackle to defend against Baltimore Colts' defensive lineman Bubba Smith. Bob Talamini replaced Herman at right guard and Sam Walton, a rookie, was benched.
Herman's ability to neutralize the pass rush of Bubba Smith enabled Joe Namath to enjoy a solid game passing, hitting on 17 of 28 passes. It also helped open the running lanes for Jet fullback Matt Snell, who rushed for 121 yards as the Jets beat the heavily favored Colts 16-7.
While Joe Namath is known for "guaranteeing" the Jets' Super Bowl III victory, Dave Herman's performance against Bubba Smith and others on the Colts' defensive line helped make the cocky quarterback's pregame boast a reality. The Jets' offensive line play was a deciding factor in the team's Super Bowl III victory.
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