Ways to add javascript files dynamically in a page

Question

I have seen Scriptaculous.js file to include its required javascript files dynamically. Is there any better approach to include javascript dynamically.

For example,

Answer 1

there are many different ways, but the way Google loads additional scripts is like this:

function getScript(src) {
    document.write('<' + 'script src="' + src + '"' +
                   ' type="text/javascript"><' + '/script>');
}

This is taken directly from Google maps loader.

Writing a script tag directly to the document is the simplest and most efficient way.