Responsive Images - Approach 2

Note: this approach is not quite as good as approach A, but it may be preferable if your filenames are not predictable (such as filename.jpg vs filename.large.jpg).

In supported browsers, the following image will load either small or large version depending on screen resolution, making a single 1kb request before requesting the appropriate size.

Read more about this here: Responsive Images 2 Readme

Photo credit (CC): Cia de Foto Flickr Creative Commons