note

Note is a term with several related senses. In general use, it denotes any short written message, annotation, or remark intended to convey information or remind someone of something. The word derives from Latin nota meaning mark or sign. In finance and law, the form of writing can take specific legal definitions such as promissory notes or banknotes.

In music, a note is a symbol placed on a staff that indicates pitch (frequency) and, in most cases, duration. Note shapes (whole, half, quarter, eighth, etc.) represent different lengths; the pitch is determined by the note’s vertical position on the staff, altered by accidentals like sharps or flats. Notes are combined with rests to indicate rhythm; tempo and time signatures further structure performance.

A banknote (or bill) is a unit of paper currency issued by a country's central bank. A promissory note is a written promise to pay a specified sum to a named person or bearer, often used in lending and commercial transactions. Negotiable instruments laws govern their transfer and enforcement.

In writing, a note can be a brief message, comment, or annotation added to a document. Note-taking is the practice of recording information from lectures, readings, or conversations. Notes can be personal reminders or public annotations used to clarify or guide readers.

In computing and digital media, notes are often stored in note-taking applications, databases or wikis as a way to organize information, tasks, and references. The concept of notes also appears in notation systems across disciplines, serving as shorthand to capture essential information.