Sorry if this is basic, but what does tagged pdf mean?

My university asked me to submit a tagged PDF of my report and I have no idea what that means. Is it a different kind of file, or just a setting in the same one? Sorry if it’s a dumb question.

had the same confusion last month. tagged pdf is just your regular pdf with extra tags added for accessibility, like so screen readers know what’s a heading. same file type, not something new. you usually get it by exporting from word with the right options ticked. tbh universities ask for it so everyone can read the report.