Zettel is a German word that translates to "note" or "slip of paper" in English. It often refers to a small piece of paper used for jotting down thoughts, reminders, or important information. In academic contexts, Zettel can also refer to a collection of notes or a system for organizing ideas. In philosophy, particularly in the works of Ludwig Wittgenstein, Zettel refers to a specific text that presents a series of thoughts and reflections. This text is part of his later philosophy, focusing on language, meaning, and the nature of understanding. Zettel serves as a way to explore complex ideas in a more accessible format.