A commonplace book is a personal collection of notes, quotes, observations, and information that an individual finds meaningful or worth remembering.
People have recorded passages from their reading, personal reflections, recipes, prayers, or anything else they wanted to preserve and revisit. The books serve as both a memory aid and a way to organize knowledge.
Today, people still keep commonplace books, both in physical notebooks and digital formats. The practice is similar to modern note-taking systems like Zettelkasten or personal wikis.