Haml!

Haml (HTML Abstraction Markup Language)

「Haml is a markup language that’s used to cleanly and simply describe the HTML of any web document, without the use of inline code. Haml functions as a replacement for inline page templating systems such as PHP, ERB, and ASP. However, Haml avoids the need for explicitly coding HTML into the template, because it is actually an abstract description of the HTML, with some code to generate dynamic content.」

So what does haml looks like?

haml:

    %one
      %two
        %three Hey there

html:

    <one>
      <two>
        <three>Hey there</three>
      </two>
    </one>

Haml doesn't use close tag such as </xxx>. Therefore, indentation is so important. At the beginning, the haml code was not easy to read, but eventually I got used to it gradually.