I apologize for asking basic questions, but I have been stuck on this one for a whole week. As a historian, I’m mostly using Elena Razlogova’s “Doing History in Obsidian and Zotero” as my startup guide for my new vault. However, trying to come up with a systematic method of indexing my notes is totally stumping me. She seems to use fields, only, for metadata for one category of sources, and to use both YAML frontmatter and fields for some other sources. Here are screenshots from one example note she published in the latter category, using both. Why would you set up a vault like this? Where do these categories of data overlap, or not? etc.