An introduction to JavaScript

Welcome

JavaScript is the third of the three technology layers of the Web Standards Model. We often refer to it as the “Behaviour” layer. JavaScript differs from both HTML and CSS because it is an imperative language. HTML and CSS are declarative languages, which means that we use them to tell the browser what we want, and the browser looks after the detail of how that is achieved. By contrast, we use JavaScript to tell the browser exactly what to do and how to do it.