[koliber]

I don't remember the details.

I think they were GIFs. From what I recall, I read the entire images as they were on disk and pushed them down the stream.

Someone mentioned https://en.wikipedia.org/wiki/MIME#Mixed-Replace and that is ringing a tiny bell.

Honestly, it was 23 years ago and I forgot the exact details. I still remember the meeting though. The feeling of dread, excitement, and ridiculousness of knocking out such a powerful machine (at the time) in order to server animated smiley faces.

Nowadays, I knock out powerful machines doing slightly more useful things.