I'm trying to figure out how the rear cassette is put together, and I found this related question that suggests at least maybe the lowest gears can be replaced. I'm trying to figure out if in general any and all of the cogs in a rear cassette can be swapped out with new replacements should any get damaged or worn? I imagine some may be designed to be an all or none deal, but if one's rear cassette supports replaceable cogs what would be the giveaway to do a visual inspection for?
This question is also distinct from Is it practical to replace two sprockets on a cassette? where the focus is on practicality of replacement but not so much of how to discover if replacement is applicable to a given cassette. It's also distinct by relating to the whole cassette in general with respect to all of its cogs.