Images are some of the most important pieces of information on the web, but over the web’s 25-year history, they haven’t been very adaptable at all. Everything about them has been stubbornly fixed: their size, format and crop, all set in stone by a single sr.
HTML authors began to really feel these limitations when high-resolution screens and responsive layouts hit the web like a one-two punch. Authors — wanting their images to look crisp in huge layouts and on high-resolution screens — began sending larger and larger sources to everyone; the average size of an image file ballooned; very smart people called responsive web design “unworkably slow“.
Images have been the number one obstacle to implementing truly adaptable and performant responsive pages — pages that scale both up and down, efficiently tailoring themselves to both the constraints and the affordances of the browsing context at hand.