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Initially, JavaScript was called LiveScript. JavaScript got its name from Netscape's support of Java applets within its
browser.
The first edition of the ECMA-262 specification was published in June 1997 by ECMA International. The second edition
was published in June 1998, a year after some changes were made to conform to the ISO/IEC-16262 standard. The
most common edition of ecma-262 at the moment is the third edition. The fourth version of the ECMAScript standard
has not been published and is not used in everyday life. In December 2009, the ECMAScript standard's fifth edition was
made available. ECMAScript 5.1, which was released in June 2011, is the most recent edition.
Features of JavaScript
JavaScript is one of the most popular languages and includes numerous features when it comes to web development.
Some important features of JavaScript are as follows:
Ð ÐLight Weight Scripting Language: JavaScript is a lightweight scripting language because it is made for data handling
at the browser only. Since it is not a general-purpose language so it has a limited set of libraries.
ÐPlatform Independent: JavaScript is platform-independent, or portable, which simply means that you can write the
Ð
script once and run it anywhere at any time.
Ð ÐDynamically Typed Language: The JavaScript programming language supports “Dynamic Typing,” which means that
the variable types are determined by the stored value. For example, if you declare a variable named “x” you can
store any type of value in it, such as a string, array, or int. This is known as “Dynamic Typing.”
Ð ÐPrototype-based Language: JavaScript is a scripting language based on prototypes. This means that JavaScript uses
prototypes rather than classes or inheritance. In programming languages such as Java, we first create a class and
then objects for that class. However, in JavaScript, we define an object prototype and then use this object prototype
to create additional objects.
Ð ÐFunctional Style: JavaScript uses a functional approach; objects are created using constructor functions, and each
constructor function represents a distinct object-type. Functions in JavaScript can also be used as objects and
passed to other functions.
Ð ÐInterpreted Language: JavaScript is an interpreted language, which means the script written inside JavaScript is
processed line by line. These scripts are interpreted by the JavaScript interpreter, which is a built-in component of
the Web browser.
Ð ÐBrowser Support: JavaScript is supported by all the browsers used nowadays. There is no need to install any external
software to execute the code of JavaScript.
There are some benefits and drawbacks to using JavaScript. Many of these are due to the fact that JavaScript is frequently
executed directly in a client’s browser. However, there are other ways to use JavaScript that provide the same benefits as
server-side languages.
Advantages of JavaScript
Some of the advantages of using Java Script are as follows:
Ð ÐIt is faster than other scripting languages because it runs within the client’s browser.
Ð ÐIt reduces server load because it runs on the client side.
Ð ÐIt is popular, which is one of the main advantages of JavaScript because you can get help for your projects from
online tutorials and forums.
Ð ÐIt has the ability to insert dynamic text into an HTML page.
Ð ÐIt has the ability to read and modify the contents of an HTML element.
ÐIt is still one of the capable scripting languages used to create visually appealing web projects. You can add features
Ð
like drag-and-drop and components like sliders, which will greatly improve the interface and give the site a more
professional appearance.
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