What is Javascript?

It is a dynamic programming language created by Netscape and used in web browsers. It is based on the use of coding syntax similar to the Java language.

First of all, JavaScript is a scripting language. A script literally means something written; however, in computer terminology, a scripting language refers to blocks of code that trigger and control applications. In this sense, JavaScript can be described as an indispensable interactive programming language for web developers.

By interaction, we mean that scripting languages enable users to actively trigger events within applications. For example, displaying a message when a user clicks the mouse is one of the simplest cases. Thousands of other behaviors and event-based actions can be triggered using JavaScript. Web browsers used on Windows or Linux systems generally perform similar functions.

No matter how broad the behaviors provided by browsers are, they are ultimately predefined behaviors. JavaScript works on and manipulates these behaviors. For instance, moving an image from right to left on a webpage, displaying another image after one image, enlarging an image when hovered over, and many similar dynamic actions fall within the browser’s domain.

These functions are carried out through web browsers. JavaScript contains the functions responsible for triggering and managing such events. It should not be confused with the Java programming language. Java is used to develop desktop and mobile applications, whereas JavaScript is primarily intended for web programming.

This programming language was created and released in 1995 by Netscape Communications. Today, it is used in almost all advanced websites. When it was first introduced, many people frequently asked what JavaScript was, since not all browsers supported it at the time.

Despite this, its capabilities quickly became recognized worldwide. Its value has continued to grow over time, and development of JavaScript has progressed continuously. JavaScript is a client-side programming language. This means that running JavaScript code does not require setting up a server or purchasing server hosting.

You can simply write your script code, save the file with an extension such as “.htm” or “.html,” and double-click the file to run it. The code is interpreted by web browsers on the client computer. There is no need for a server system such as ASP.NET or PHP. In this respect, JavaScript is both interactive and client-side. With HTML alone, you cannot provide users with decision-making or interactive capabilities.

To achieve interaction, you must use an interactive programming language. Languages such as ASP.NET and PHP are interactive but require server-side compilation. JavaScript does not require this. However, JavaScript can also run on the server side in certain cases. Complex systems such as game websites and advanced web applications may use server-side JavaScript, providing additional flexibility.

 

Relationship Between JavaScript and Java

Although JavaScript and Java share some similarities, they are fundamentally different languages. JavaScript is a dynamic scripting language that supports prototype-based object creation. It does not have Java’s static typing system or strong type control. JavaScript’s basic syntax was intentionally designed to resemble Java and C++ to make it easier to learn by reducing the number of new concepts.

JavaScript is object-based, and there is no strict distinction between object types. Inheritance continues through the prototype mechanism, and properties and methods can be dynamically added to any object. Java, on the other hand, is class-based. Objects are divided into classes and instances, and inheritance follows a class hierarchy. Classes cannot dynamically receive new properties or methods. In JavaScript, variable data types do not need to be explicitly declared, whereas in Java, variable types must be defined.

 

Relationship Between JavaScript and DOM

DOM is not a programming language nor is it designed exclusively for JavaScript. DOM is an API for HTML and XML documents that connects web pages to scripting and programming languages.

Every element in a document—such as headings, tables, table cell text, the document itself, and buttons—is part of the Document Object Model. DOM (Document Object Model) represents a document or webpage as a structured group and defines how a scripting language like JavaScript can access and manipulate webpage nodes.

As understood from the definition, JavaScript uses the Document Object Model to access elements within a document and perform operations on their content or properties.

 

Relationship Between JavaScript and DHTML

The shortest definition of Dynamic HTML is:
(X)HTML + JavaScript + DOM + CSS = DHTML

DHTML (Dynamic HTML) is not a new definition of HTML or JavaScript, nor is it a new scripting or programming language. DHTML refers to the enhanced use of JavaScript dynamism to make webpages more organized, detailed, and visually engaging.

Within DHTML, the DOM creates a structural model of the (X)HTML page, enabling scripting languages to access objects. CSS defines visual aspects such as text colors, fonts, background colors, background images, and object positioning. JavaScript enables the dynamic use of DOM and CSS.

For example, consider the menus you frequently encounter on websites. When you hover over a menu option with your mouse, JavaScript detects the pointer and modifies DOM and CSS properti