[lxgr]

> .DS_Store files come from Apple's file systems containing a separate data and resource fork

No, that would be ._<filename> files (containing resource forks, when the corresponding file is stored on a volume with a FS not supporting them natively), which are much rarer these days given that resource forks are not really used anymore.

.DS_Store contains Finder metadata, as far as I know (non-default icon sorting or positioning, categories, tags etc.), and they occur on all volumes, including Mac native filesystems. Finder just hides them by default.