Niklas Luhmann collected 90,000 note cards and popularised "Zettelkasten" note-taking as a knowledge management method with paper-based hyperlinks: https://nikl

Niklas Luhmann collected 90,000 note cards and popularised "Zettelkasten" note-taking as a knowledge management method with paper-based hyperlinks: https://niklas-luhmann-archiv.de/projekt/beschreibung https://niklas-luhmann-archiv.de/projekt/beschreibung (archive, supports download as TIFF scans and JSON transcriptions). If you use Sublime (as I do beside Emacs), ther's a plug-in: https://zettelkasten.de/posts/sublime-text-plugin/ https://zettelkasten.de/posts/sublime-text-plugin/ During my undergraduate studies I summarized each paper or book I read in form of a single plain text file. This was very helpful when studying for oral exams that required internalizing in the order of >20 volumes. While these weren't cross-referenced, and no special tool was used, this still helped to ace the exams, mostly because the practice of summarizing/compressing the material to its essence itself is essentially the same as learning it. Main main advice is any tool or none is fine as long as the notes are in plain text so they can last - it's the most durable file format, and you can always build a full-text index to make it searchable e.g. using Lucene.