Picturefill

Markup

<img src="transparent.gif" alt="..."
    srcset="small.jpg 1x, small@2x.jpg 2x">
<noscript>
    <img src="small.jpg" alt="...">
</noscript>

max-width: 480px

Porsche 911 Carrera 4S (991)

Porsche 911 Carrera 4S (991) by David Villarreal Fernández (CC BY-SA 2.0)

Feature

<img> element & srcset attribute (Device Pixel Ratio)