Commonplace books were a way to compile knowledge in the days before digital memories. Essentially these were journals or scrapbooks filled with the daily findings of their authors whether quotes, letters, poems, tables of weights and measures, proverbs, prayers, legal formulas or whatnot. Commonplaces were used as an aid for remembering useful concepts or facts. Each was unique to its creator's particular interests. Latin: locus communis i.e., "a theme or argument of general application"