JavaScript is a client-side language and is therefore part of the visible web page source.  BEE can build JavaScript by outputting its code.  For example, the following build a JavaScript array variable from a BEE (server side) array:

display '<script language="JavaScript">\n';

display 'var jsCars = new Array\n';

foreach (cars as model)

   display 'jsCars["{model:key}"] = "{model}";\n';

display '</script>\n';

BEE can conditionally turned on or off section of JavaScript:

if ('{scheme%discount}')

{

display '<script language="JavaScript">\n';

display 'price = price * (1 – {scheme%discount} / 100);\n';

display 'alert("Now you can get {scheme%discount}% discount!");\n';

display '</script>\n';

}