Note-taking (sometimes written as notetaking or note taking) is the practice of recording information from different sources and platforms. By taking notes, the writer records the essence of the information, freeing their mind from having to recall everything. Notes are commonly drawn from a transient source, such as an oral discussion at a meeting, or a lecture (notes of a meeting are usually called minutes), in which case the notes may be the only record of the event. Since the advent of writing and literacy, notes traditionally were almost always handwritten (often in notebooks), but the introduction of notetaking software and websites has made digital notetaking possible and widespread. Note-taking is a foundational skill in personal knowledge management.

Note-taking has been an important part of human history and scientific development. The Ancient Greeks developed hypomnema, personal records on important subjects. In the Renaissance and early modern period, students learned to take notes in schools, academies and universities, often producing beautiful volumes that served as reference works after they finished their studies. In pre-digital times, people used many kinds of notebooks, including commonplace books, accounting waste books, and marginalia. Philosopher John Locke developed and published a popular indexing system which served as a model for commonplace books and inspired at least ten different published editions of commonplace book templates in Europe and the Americas as well as Bell's Common-Place Book, Form'd Generally upon the Principles Recommended and Practised by Mr Locke (London, 1770).

Note-taking is a central aspect of a complex human behavior related to information management involving a range of underlying mental processes and their interactions with other cognitive functions. The person taking notes must acquire and filter the incoming sources, organize and restructure existing knowledge structures, comprehend and write down their explanation of the information, and ultimately store and integrate the freshly processed material. The result is a knowledge representation, and a memory storage. Studies comparing the performance of students who took handwritten notes to students who typed their notes found that students who took handwritten notes performed better on examinations, hypothetically due to the deeper processing of learned material through selective rephrasing instead of word-for-word transcription which is common when typing notes.

Note-taking is a good strategy to enhance learning and memory, as it allows the notetaker to be selective and reorganize ideas during a lecture. These notes can be reworded in an easier way that will facilitate the understanding of the content taught in class. Afterward, the notes can be used to help process, recall, and use information that has been rapidly gone through during the lecture.

Taking notes on different words used in lectures fosters vocabulary learning and stimulates autonomous learning of actively engaged individuals.

Many different formats are used to structure information and make it easier to find and to understand later. The format of the initial record may often be informal and/or unstructured. One common format for such notes is shorthand, which can allow large amounts of information to be put on paper very quickly. Historically, note-taking was an analog process, written in notebooks, or other paper methods like Post-It notes. In the digital age, use of computers, tablet PCs and personal digital assistants (PDAs) is common.

The note taker usually has to work fast, and different note-taking styles and techniques try to make the best use of time. The average rate of speech is 2–3 words per second (which is 120-180 words per minute), but the average handwriting speed as only 0.2–0.3 words per second (which is 12-18 words per minute).

Regardless of the medium, note-taking can be broadly divided into linear and nonlinear methods, which can be combined.