Java vs. JavaScript
Despite the word “java” in the name, JavaScript is a different language than Java, albeit with some similarities.
A JavaScript program is written directly into the HTML page, and is executed by the JavaScript intrepeter, so also executes dynamic web page content in the browser window.
JavaScript is special purpose - it is an object-based language that deals directly with browser entities such as windows, textfields, forms, frames and documents.
JavaScript can respond to browser events such as mouse clicks and user-typed text.
JavaScript is easy and fast to write, but not as powerful as Java.
Client side with dynamic HTML, JavaScript can be more effective than Java