Squeeze PNGs to the smallest files browsers open

AVIF is the current frontier of image compression: photographic content drops below even WebP, often dramatically below PNG, while modern browsers render it natively. That makes it the pick for image-heavy sites where transfer size decides load time. Two honest caveats: encoding is noticeably slower than other formats, and software older than a few years may not open the files. For web delivery both usually cost nothing; the conversion runs locally either way.