Responsive web design is the newest craze for websites, and blogs. Responsive design is when a website or blog adapt to screen sizes. However, known to many if you set CSS’s max-width to 100% they can create a responsive layout, but the truth is, mobile sites will still be downloading full size images. This can be an issue especially when users visit your WordPress blog because they will have to wait for a long time for your images to show.
Interested? Then you might want to check out this blog to know how to use Picturefill.