The HTML is parsed, JavaScript is executed, and the result is the DOM. The content of a web page is not (just) source code, it’s the DOM. This makes it pretty important.

"For fun," he built a complete PC emulator in JavaScript, and then used it to run a fully functioning version of Linux in a web browser. How did it turn out?

Servlets are mainly used as widgets on websites that run advanced applications not available in simple HTML or JavaScript. To execute a servlet in Netbeans, you use the debugger to run the scripts ...