JavaScript is a scripting language for expanding HTML

JavaScript is a compact scripting language for expanding the HTML command set which also makes it possible for developers with little programming knowledge to implement object-oriented applications in web pages. In other words, JavaScript is a programming language that is embedded in websites as additional technology. The JavaScript programs are interpreted in the web browser. This means that they are translated into machine code and executed. Since JavaScript runs on the computer of the web surfer, it is referred to as a client side programming language, to differentiate it from programming languages that run on the web server, such as PHP or Perl scripts. JavaScript is directly integrated into the HTML document, which makes fast action times are possible as a result. You do not need any additional editors to develop JavaScripts such as AppBuilder, compilers, debugger or any other development environments. JavaScript can be easily entered into text editors like HTML code.

JavaScripts have access to the browser window and to the HTML document displayed within. Their most important task is to respond to user input in the document; JavaScripts can then make changes to the HTML document currently being displayed. These changes only take place in the browser – the memory of the computer – while the document on the web server remains untouched. JavaScript only shares part of its name and structure with the programming language Java. Java is also an object-oriented scripting language, but can also be used for small, stand-alone applications and is also harder to learn. JavaScript cannot run on its own, it needs an HTML environment.

JavaScript has interesting expansions for HTML

JavaScript brings many useful expansions to HTML, such as the verification of forms, calculating mathematical formulas or also effects such as rotating contents, modifying multiple screens at the same time or publishing additional information, for example with links. Along with the introduction and widespread use of JavaScript, it also brought negatives to the computer screen, such as opening pop-up windows.

AngularJS, Dojo Toolkit, Ext JS, jQuery, MooTools, Prototype, Qooxdoo and the Yahoo User Interface Library are some of the well-known JavaScript libraries and frameworks. First and foremost, you have Moo.fx and for graphic effects. Node.js provides its own libraries and frameworks for server side programming.

You can find more information on JavaScript on Wikipedia: