Key difference: DHTML is essentially Dynamic HTML. It is a new way of looking at and controlling the standard HTML codes and commands. DHTML is a collection of technologies that are used to create interactive and animated web sites. Even though their names suggest that Java and JavaScript must be related somehow, it is just not true. JavaScript is an interpreted computer programming language. The main difference between Java and JavaScript is that while Java is a programming language, JavaScript is scripting language.

DHTML is essentially Dynamic HTML. It is a new way of looking at and controlling the standard HTML codes and commands. DHTML is a collection of technologies that are used to create interactive and animated web sites. DHTML gives more control over the HTML elements. It allows one to incorporate a client-side scripting language, such as JavaScript, a presentation definition language, such as CSS, and the Document Object Model in HTML web pages. 

DHTML also allows the pages to change at any time, without returning to the Web server first. It allows scripting languages to change a web page's look and function after the page has been fully loaded and during the viewing process. It also allows the user to add effects to their pages that are otherwise difficult to achieve.

Wikipedia list additional DHTML features, such as DHTML allows the developers to:

• Animate text and images in their document, independently moving each element from any starting point to any ending point, following a predetermined path or one chosen by the user.
• Embed a ticker that automatically refreshes its content with the latest news, stock quotes, or other data.
• Use a form to capture user input, and then process, verify and respond to that data without having to send data back to the server.
• Include rollover buttons or drop-down menus.

Even though their names suggest that Java and JavaScript must be related somehow, it is just not true. JavaScript is an interpreted computer programming language. The main difference between Java and JavaScript is that while Java is a programming language, JavaScript is scripting language. It is a prototype-based scripting language that is dynamic, weakly typed, and has first-class functions. However, like Java, JavaScript is heavily influenced by the C programming language. JavaScript also borrows many names and naming conventions from Java, but it does have very different semantics than Java.

JavaScript takes its key design principles from the Self and Scheme programming languages. It is a multi-paradigm language that supports object-oriented, imperative, and functional programming styles. JavaScript consists of three parts - Core, BOM (browser object model), and DOM (document object model).

JavaScript was formalized in the ECMAScript language standard and was originally implemented as part of web browsers. It allowed client-side scripts to interact with the user, control the browser, communicate asynchronously, and alter the document content that was displayed. However, JavaScript is also used in applications outside of web pages, such as in PDF documents, site-specific browsers, and desktop widgets. Furthermore, newer and faster JavaScript VMs and frameworks have also increased the popularity of JavaScript for server-side web applications.

There are various similarities between Java and JavaScript, such as both have a C-like syntax. They are both object-oriented and typically sandboxed, especially when used inside a browser. Also, JavaScript was designed with Java's syntax and standard library in mind. 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. However, they are much more different than they are similar.

The difference between DHTML and JavaScript:

• DHTML is essentially Dynamic HTML. JavaScript is an interpreted computer programming language.
• DHTML allows one to incorporate a client-side scripting language, such as JavaScript, a presentation definition language, such as CSS, and the Document Object Model in HTML web pages. 
• A DHTML page uses JavaScript to dynamically respond to the user's interactions.
• DHTML is not an individual technology. It is the product of three related technologies: HTML, Cascading Style Sheets (CSS), and JavaScript.

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