What is WebM?

Google's royalty-free video container, built for the web and carrying VP8, VP9 or AV1 video with Opus audio. Every modern browser plays it without a plugin or a licence, which is why it's the sensible choice for video you host yourself and a poor one for video you send to someone's phone.

What is AIFF?

Apple's uncompressed format, the Mac counterpart to WAV, and still what Logic and older Pro Tools sessions expect. Its one genuine oddity is storing the sample rate as an 80-bit extended float, a data type almost nothing else in computing still uses.