We’re not there yet, but hopefully soon!
Basically, the image format, webP, has a far-better compression rate than any other existing image format, but it isn’t widely supported yet. There is also a new CSS background-image spec coming that allows developers to do something like this:
background-image: image("whatever.webp" format('webp'), "whatever.jpg");
* Note the use of
Again, not ready yet, but coming. Cool.