Output: The results of executing the CSS, HTML, and JavaScript entered into the sections of the page. Figure A shows jsFiddle loaded in Internet Explorer 9 with empty code panes.

It doesn’t care what back end you use, so long as it produces HTML.” To get a feel for how it works, let’s look at a TODO example that uses Express, along with the Pug HTML templating engine.

You may already know that CSS is a vital technology for styling your web pages. But you don’t need to use it, and your sites can still look good without it.